Modernizing US-Japan Command & Control Relationships for New Challenges | NEXT Alliance Conference Summary: Tokyo 2023

Mr. James Schoff
Sasakawa USA Senior Director

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The Spring 2023 NEXT Alliance Conference (NAC) explored potentially useful adjustments to future US-Japan command and control (C2) relationships, in light of three pressing trends: 1) a shifting regional military balance that makes integration of allied forces more vital to sustaining deterrence or repelling any attack; 2) a combination of technological advances and operational needs that are driving toward more integrated and combined force concepts; and 3) Japan’s efforts to expand its defense capabilities and improve military “jointness,” such as developing a counterstrike capability and introducing a permanent joint headquarters for its Self-Defense Forces (SDF). Alliance C2 modernization has occurred in a modest and piecemeal fashion over the years, but a more comprehensive update to these 1960’s-era C2 arrangements is needed.

Spring NAC 2023 (convened in Tokyo from March 10-13) was attended by around 40 American and Japanese specialists from government, the military, academia, think tanks, and the private sector engaging in a series of discussions over a long weekend. It included briefings from Japanese government officials on different security topics including a new national defense strategy, Japan’s defense buildup plan, and national security strategy, followed by a two-day workshop, media briefing, and a site visit to Yokota Air Base. The Spring 2023 NAC is one of two offsite “retreats” convened each year by Sasakawa Peace Foundation USA focused on a priority issue area for the US-Japan NEXT Alliance Initiative.

The objective of this NAC was to foster substantive bilateral expert dialogue on complex issues surrounding C2 relationships within the alliance, and to support greater mutual understanding and broader public awareness of these issues. Specifically, we focused on 1) the C2 structure we have, 2) models of alliance C2, 3) political, legal & institutional considerations, and 4) C2 needs for the future. The following NAC summary is the author’s understanding of what was discussed and diagnosed over the four days. It is not a consensus document, and this not-for-attribution style is designed to respect the ground rules for the bilateral dialogue.

Table of Contents:

  1. Background and Introduction
  2. Sizing Up the Needs, Challenges, and Opportunities
    • Opportunities
    • Challenges
    • Needs
  3. Key Themes and Considerations
    • Japan’s Permanent Joint Headquarters (PJHQ)
    • Defense of Japan versus Regional Contingency
    • Information Sharing and Cybersecurity
    • Bilateral versus Minilateral Connectivity
  4. Three Basic Options for Alliance C2 Modernization
    • Building Blocks
    • Bilateral Staff Approach with JTF-Japan
    • Bilateral Command Approach with JTF-Japan
  5. Interim Conclusion and Next Steps

1. Background and Introduction

This “Task Force” project was launched in 2022 by NEXT at Sasakawa Peace Foundation USA on the premise that two trends are complicating current US-Japan command and control (C2) arrangements in ways that undermine their effectiveness, while a third is creating opportunities for closer bilateral security cooperation when we need it most. The first trend involves a shifting regional military balance that makes integration of allied forces more vital to sustaining deterrence or repelling any attack.  The second trend includes a combination of technological advances and operational needs that are driving toward more integrated and combined force concepts. These go beyond “multi-domain” models of operating in parallel and lead to a deeply interconnected operating system influenced by digital transformation. Additionally, Japan’s own consideration of new capabilities, including long-range precision strike, will call into question the longstanding alliance division of labor in roles and missions and prompt a reconsideration of alliance C2. At the same time, Japan is focused on improving military “jointness” and moving to create a permanent joint headquarters for the Self-Defense Forces (SDF) in the next year or two, opening up new opportunities.

All this suggests that a reexamination of US-Japan command relationships is needed urgently, to consider practical and useful adjustments to SDF connections with US Forces Japan (USFJ) and US Indo-Pacific Command (INDOPACOM) so that bilateral arrangements can align effectively with national reforms. It can also help with timely decision making on defense policy and deployment issues, as Japanese territory (and US bases therein) are more connected with regional military operations compared to before. Japan is a front-line state in any regional conflict, and Russia’s invasion of Ukraine has demonstrated the need to be truly prepared for potential conflict. Sustaining deterrence in East Asia requires more effective leveraging of US and Japanese military capabilities in an integrated manner, but this can only happen if the allies have a sophisticated bilateral command structure that combines shared situational awareness with timely decision making and seamless execution of well-coordinated action.

Task Force participation has been flexible to date (i.e., different experts join and depart the dialogue, with some consistent core members) and involves a wide range of specialists with varied expertise. The purpose is to engage US and Japanese defense communities in discussions about the dual challenge to the existing command structures (described above), and to consider elements in potential design of a more integrated alliance C2 system that offers the operational benefits of a more unified command while respecting legal, political, and institutional limitations (i.e., unity of effort, if not unity of command). During 2022, we convened a series of small hybrid Track 2 and Track 1.5 roundtable dialogues to inform the design of our 4-day event in Tokyo. Not-for-attribution summaries of these roundtables are published on the Sasakawa USA website (under the “Defense Cooperation” section of “Research Areas” on the NEXT Alliance Initiative webpage). Additional follow-on roundtables will be convened in 2023, culminating in a second NAC in Annapolis this Fall and a final written report in 2024.

2. Sizing Up the Needs, Challenges, and Opportunities

Overall, no NAC participant questioned the need for modernizing alliance C2 arrangements to some extent, given the trend lines outlined above. As one retired US military officer at the NAC noted, “the primacy of getting Command and Control right cannot be over emphasized as critical to both our countries.  Command and Control structures, and the authorities they are given, are THE critical element in a nation’s decision cycle that empowers and applies national power to counter direct threats to their national security during times of crisis and conflict.”

He added, “it ultimately is the framework that drives the process of: 1) thinking strategically, 2) planning using operational level coordination frameworks, and then 3) acting tactically to create the effects called for in the operational framework that will deliver the national strategic vision.  What I see too often are nations thinking, planning, and acting tactically, and then questioning why they can’t get out ahead of the competition.”

The main focus of NAC dialogue therefore related to three questions: 1) what an ideal modernized C2 framework might be (i.e., what are the most important needs to address); 2) what are the practical challenges to realizing this goal; and 3) are there opportunities to help steer alliance integration in a more productive direction?  Some of these questions are addressed in more detail in section 3 (Key Themes and Considerations), but they are summarized briefly below.

2.1 Opportunities

On the third point (opportunities), a US government official with extensive experience in Japan offered a view that “we are dealing with a very different Japan now,” and that on the security front there has been “more change in the past two years than in the 23 that preceded it.” The official suggested that it was “the specter of authoritarian aggression…[that] created unique political space” for leaders in Tokyo and Washington to drive much needed reforms, to the point that “modernizing Alliance coordination, command, and control will represent a central effort of our Roles, Missions, and Capabilities policy dialogue in the years to come.”

In addition, at multiple points throughout the long weekend, participants highlighted the benefit of alliance experience during OPERATION TOMODACHI in support of Japan’s response to the 2011 earthquake, tsunami, and Fukushima nuclear crises. During this “critical stress test of the Alliance,” one US official observed, we saw “the utility of having an operationally empowered Joint Task Force (JTF) commander located in Japan, responsible for bilateral operations and coordination under the direct authority of the INDOPACOM commander” (see Figures 1 & 2).

Moreover, as one former Japanese military officer involved in the response noted, “the strong personal bonds between the SDF and the US military and the foundation of mutual trust among their defense communities were critical for facilitating information sharing.” That said, he added that “while human relationships of trust and confidence are a great help during a crisis, they alone are not enough, and we must have a good structure and system in place if we are to respond adequately to the security challenges we face today.” He highlighted in particular the lack of shared awareness or intelligence about conditions at the Fukushima nuclear plant and difficulties communicating in depth to develop a truly “shared understanding” of various crisis situations.

Fig 1. Structure of US Joint Support Force for Disaster Relief in 2011[1]

Fig 2. Basic Coordination Mechanism for JSDF-US Military during OPERATION TOMODACHI[2]

Of course, the main reason why the ad hoc creation of a US Joint Support Force was necessary in the first place is because US Forces Japan (USFJ) was never intended to command or control the majority of the 54,000 service personnel assigned to Japan. With a staff of about 140 people, USFJ is less than half the size of the US Embassy in Tokyo, which has almost the same number of active-duty military personnel as USFJ.[3] USFJ’s stated mission is to “manage the US-Japan Alliance and set conditions within Japan to ensure US service components maintain a lethal posture and readiness to support regional operations in steady state, crisis, and contingency, and that bilateral mechanisms between the United States and Japan provide the ability to coordinate and synchronize actions in support of the US-Japan Alliance.”[4]

Sticking with the theme of opportunities, participants noted that Japan’s planned establishment of a new Permanent Joint Headquarters (PJHQ) is an opening to coordinate differently by streamlining points of contact and responsibilities. Currently, Japan’s Chief of Staff, Joint Staff has multiple US counterparts in addition to splitting his responsibilities between advising the defense minister and making sure the minister’s orders are carried out. The unwieldiness of this arrangement during crisis was why three days into Japan’s SDF mobilization to respond to the Great Eastern Japan Earthquake in 2011, the Defense Ministry ordered its first large-scale Joint Task Force (JTF) to manage operations, led by the Northeastern Army Commander.[5]

The OPERATION TOMODACHI experience is instructive, because as one US workshop participant put it, although “the INDOPACOM Commander, in principle, should play [the] role [as a one-stop operational and policy coordination shop]…in reality he is responsible for 35 other countries as well.” A similar dynamic exists with Japan-based US commands in that their responsibilities extend well beyond Japan. The US 7th Fleet based at Yokosuka, for example, has a 124-million square kilometer area of operations throughout Asia, and the III Marine Expeditionary Force (III MEF) based in Okinawa has in the past supported military operations in Iraq, Afghanistan, Somalia, and other nations. Another US (retired) military participant added that, while he has seen Japanese org charts suggesting a simple link between Japan’s standing JTF headquarters commander to the INDOPACOM Commander, “I do not believe this is realistic.” He explained that “when activated, INDOPACOM is often established as a Joint Force Command…I have never seen them established as a JTF Commander.”[6]

Indeed, in that time of crisis in 2011, both countries moved quickly to augment their C2 relationships for a more efficient and effective approach for OPERATION TOMODACHI by linking their newly created JTFs on the fly. One US workshop participant expressed hope that “Japan’s PJHQ can serve as a docking station for a new US C2 structure [for the future] that would operationally manage all US forces in Japan—planning in peacetime and commanding in crisis.”

Other opportunities for the alliance include all the incremental adjustments and adaptations it made over the past several years to improve its operational efficiency and bilateral synergy. Notable among these were the standing up (and subsequent investment in) the Bilateral Joint Operations Coordination Center (BJOCC) at Yokota Air Base in 2006 and the 2015 Defense Guidelines revision that led to creation of the Alliance Coordination Mechanism (ACM) and Bilateral Planning Mechanism (BPM) (see Figures 3 and 4).[7]  The ACM framework includes a Bilateral Operations Coordination Center (BOCC) and Component Coordination Centers (CCCs), when needed. These “centers” are utilized when conducting operational coordination related to activities of the SDF and US Armed Forces, as well as facilitating component-level bilateral coordination. Examples include the response to the Kumamoto Earthquake of 2016, ballistic missile launches by North Korea, and Chinese activities in the waters and airspace around the Senkaku Islands.[8]

Fig 3. Alliance Coordination Mechanism (ACM) Framework[9]


More recently, in late 2022 the allies established a US-Japan Bilateral Information Analysis Cell (BIAC) at Yokota Air Base to jointly analyze and process information gathered from assets of both countries in support of mutual security cooperation.[10] As one USFJ service member described it, with about 30 specialists co-located sharing information and analysis, “we each get a full capability with only half the investment.”[11]

Fig 4. Bilateral Planning Mechanism (BPM) Framework[12]


Finally, NAC participants frequently echoed the alliance sentiments expressed in the US-Japan Security Consultative Committee (or 2+2) statement from January 2023 that began by “recognizing the convergence of [our] nations’ new national security and defense strategies toward bolstering deterrence in an integrated manner” and “confirmed unprecedented alignment of their vision, priorities, and goals.” This perception is much deeper than a press release talking point and reflects the most significant alignment to date for the US and Japan in their thinking, planning, and actions regarding the protection of national security. It represents a clear opportunity for the two governments to modernize their C2 arrangements to accommodate these changes and maximize mutual benefit.

2.2 Challenges

For all the opportunities that make alliance C2 modernization more feasible than ever before, there are still numerous challenges to overcome. One overarching challenge is a mismatch between the authorities that rest within each side’s military when it comes to the use of force, derived from underlying differences in the allies’ legal frameworks. In contrast to the US legal basis for military operations that derives from the executive power of the president, Japan’s SDF can only act pursuant to the national legislature (known as the Diet).[13] As such, C2 functions in Japan are based on articles 65 and 72 of the Constitution, which vests executive power in the cabinet and empowers the prime minister to represent the cabinet and submit bills to the Diet for the “exercise of control and supervision over various administrative branches” (including the SDF).[14]

A retired Japanese military officer at the NAC workshop described the process for two situations when the SDF is allowed to conduct full military operations, either an “Armed Attack Situation” (i.e., “organized and premeditated use of force against Japan”) or a “Survival Threatening Situation” (the latter referring to an armed attack against an ally that simultaneously threatens Japan). In each case, the use of force must be a last resort limited to the “minimum necessary” amount and should be governed by a “basic response plan” prepared by the Cabinet Secretariat and approved by the Diet.[15] An outline of this process is described in Figure 5. A separate law allows the SDF to provide logistics support, search and rescue activities, and take other measures to support foreign armed forces if their actions “have an important influence on Japan’s peace and security,” but this support cannot be provided anywhere near a scene of combat or danger.[16]  The bottom line is that virtually any authorization for integrated SDF action with US forces is likely to be limited and tightly controlled by a political process.

In addition, a retired US military officer noted that legal differences between the allies extend beyond authorities and affect military accountability as well. US service members, for example, are under the legal jurisdiction of the Uniform Code of Military Justice, which makes forces accountable to their commanders and commanders accountable to civilian control. For its part, Japan’s Constitution (Article 76) vests “whole judicial power” in a Supreme Court, so SDF service members are under the legal jurisdiction of domestic courts. There is no separate military justice system. Also, Japan’s legal code does not enable prosecution of Japanese for negligence crimes committed overseas. In a variety of ways, US and Japanese legal approaches differ not only in terms of jus ad bellum, which deals with the “why” or the legitimacy of using force, but also for jus in bello (i.e., the “how” or conduct of hostilities in compliance with accepted laws of armed conflict). As such, these differences would frustrate development of a truly combined US-Japan command authority due to different governing parameters.

Fig 5. Japanese Government Process to Certify the Use of Force[17]

Moreover, a former Japanese bureaucrat at the workshop described the limitations of a “minimum template approach” and a “water-down” tendency in the Diet after draft plans or legislation is proposed, whereby already limited courses of action informed by operational need and facts on the ground are diluted further by politicians for the sake of political palatability. He suggested that this will not be remedied until the Diet agrees to shift toward a “negative list” of certain actions that cannot be carried out by the SDF instead of the current “positive list” approach that specifies a short list of allowed activities and strictly limits operational flexibility. A retired Japanese military officer described Japan’s defense policy as generally preferring “political validity” over “military rationality,” although this is beginning to change. Still, even if some gains are made in this area, it is inevitable that politicians in Japan will retain more authorities with regard to military operations than their US equivalents, creating a mismatch of delegated authority held by US and Japanese officers in the field.

The challenges are not all on the Japan side, as any alliance C2 modernization process will require some adjustments to current US approaches that could be viewed by many Americans as ill advisable for any number of reasons. As one retired US military participant explained, even extremely close and well-aligned combined C2 structures such as NATO and US-South Korea come with certain “accommodations for clearly articulated and negotiated national interests of the participant parties.” He added that “as a rule, [these accommodations] reduce the unity of effort, focus, purpose, planning and execution when compared to National Command and Control.” US policy makers and military commanders could be frustrated if they believe that C2 modernization limits their decision-making flexibility or ties up US forces and adversely impacts US readiness. INDOPACOM might not want to see some of its authority delegated to a newly structured sub-unified command in Japan, if that were to be proposed. It could take time to build consensus for a new C2 framework, even as most NAC participants urged quick action by both governments on these issues.

Another formidable challenge to highlight is the seamless and sufficient sharing of information and intelligence so that the allies have a truly common operating picture of the battlespace and exchange updates in real time with adequate security. This is a challenge for any combined or coalition C2 arrangement, but it has proven to be a slow and incremental process for the United States and Japan ever since they concluded a General Security of Military Information Agreement (GSOMIA) in 2007 and set up a companion process for information sharing improvement, the Bilateral Information Security Consultation (BISC) framework.[18] The allies have made important gains since 2007 increasing the volume and mutual confidence for information exchange, but US officials still call for continued improvements by Japan to reach greater levels of equivalency and interoperability in their approach.

Overall, the challenges to alliance C2 modernization can be categorized several different ways including legal (and in some respects, Constitutional), political, bureaucratic or institutional rigidity, cultural, and technical. This does not mean that improvements are not feasible, but it suggests that expectations should be measured. Almost any ideal alliance C2 structure drawn up on paper to meet all operational needs will run into any number of obstacles mentioned above, which will result in compromises. If those compromises are carefully considered and weighed against doing nothing, chances are good that some useful C2 modernization can be accomplished.

2.3 Needs

The most important question, however, is what is the operational problem or the operational need around which to organize alliance C2 modernization? This is the determinant behind any combined C2 design, and it is why Combined Forces Command (CFC) in South Korea is different from the biennial Exercise TALISMAN SABRE with Australia or the Joint Interagency Task Force (JIATF) South in Central America and the Caribbean. Will it be focused on a particular mission or domain, or will it involve multiple domains and an integrated set of missions? Will it be focused on a specific area of operations, or will it be nation or region wide? Is it purely a bilateral construct, or should it be adaptable to include other partners? Ultimately, these questions must be answered by the US and Japanese governments, but the NAC meetings provided some initial ideas (some of which are explored in more detail in the “Key Themes and Considerations” section).

One alliance C2 need that various participants raised several times throughout the NAC was speed. The “fight tonight” mantra borrowed from US and South Korean forces on the Korean Peninsula was echoed frequently. While most participants assessed that China and North Korea do not currently seek conflict in the region, if this changes then participants believed that their initial actions could come without warning and “hit hard” to try to deter US and allied involvement. On the Taiwan scenario specifically, one workshop participant suggested that “China will move fast and use overwhelming force, combining kinetic action with cyber-attacks, a disinformation barrage, and probably disruptive actions in the space domain.” Another participant thought that China would likely “escalate horizontally” by encouraging North Korean or Russian threats to allied interests. In this case, coordinating the combined or even coalition actions of the SDF and Japan-based US forces from Hawaii would be suboptimal.

A retired US military officer recounted his own experience with time-sensitive decision making in the region, when early warning sensors one morning picked up incoming North Korean missiles to Japan without clear targets (raising questions about whether to engage or distribute wider alerts), or when an aircraft accident at sea off the coast of Japan prompted a large-scale search and rescue operation involving US, Japanese, and Australian assets.  In both cases, valuable time was lost while communicating and coordinating between USFJ and INDOPACOM, with sometimes conflicting information and questions about “who’s in charge” about what aspect of the operation. One outcome of these experiences has been additional refinement in procedures that empower USFJ to be a “supported” command in certain situations related to missile defense and nearby search and rescue operations, but this is simply nibbling at the edges considering that the US and Japan in the future might need to fight immediately with forces already within the Joint Operations Area (JOA) around Japan.

Another C2 modernization need highlighted by NAC participants is a robust civilian-political leadership and decision-making connection between the governments and allied military forces (what some called the “seamlessness between political decision making and military action”). A retired Japanese military officer and retired government official recounted their experience during OPERATION TOMODACHI and the importance of creating the “Hosono Process” from March 22, 2011 to facilitate allied coordination. This refers to the vital role that Special Assistant to the Prime Minister Goshi Hosono played as a political leader for the Japan side in the bilateral coordinating committee with US Deputy Chief of Mission Jim Zumwalt as his counterpart.

One retired US official from that time recounted a story of some difficulty the coordination committee was having in getting sufficiently detailed information from TEPCO, the utility in charge of the disabled nuclear reactor. “At one point, the Americans were asked to leave the room,” he said, “and we heard some loud voices for a while, and when we reentered the room, TEPCO was much more cooperative.”

Drawing from the example of the Hosono Process, a Japanese NAC participant suggested some reforms to the Alliance Coordination Mechanism (ACM) including the designation of a Cabinet-level politician as the nominal head of the ACM’s Japan side “in advance, not as needed.” The ACM has always had the potential to elevate up to the top NSC levels in both countries, but to date this has been a theoretical concept not prepared for concretely.

The ACM also allows for “other relevant ministries and departments” to be involved “as needed,” but the Japanese participant saw this as another opportunity for expansion in advance. Another Japanese participant concurred, noting that “one cannot draw a clear line between military and non-military activities,” and so they both recommended adding some civilian ministries or agencies as ACM standing members (e.g., Ministry of Internal Affairs and Communications, Ministry of Land, Infrastructure, Transport and Tourism (that oversees the Japan Coast Guard), and others). An American added that “the participation of civilian agencies and officials across the alliance in this contingency planning is essential to detect, ahead of need, actions permitted and those prohibited.”

Overall, NAC participants steered away from a narrowly focused set of C2 modernization needs. They suggested that US-Japan alliance C2 in the future should be able to function across multiple domain environments and across a wide geographical area. Also, because it will need to transition smoothly from phase to phase, from peacetime all the way to an armed attack situation, there should be a permanent standing feature to alliance C2, even if it is designed to expand and contract depending on the circumstances. One retired US military officer described the “need to share a dynamic common operating picture (COP) [with friendly and enemy forces clearly identified] and align political decisions (empowerment) behind shared objectives, with well-planned and coordinated actions to achieve those objectives, leveraging our combined assets and with real-time feedback and adjustment based on developments.” A primary role for the new alliance C2 structure, one participant suggested, would be “the development of joint and combined capability through vigorous contingency planning.” An American participant added, while “ideal is the goal, optimized is the reality” towards what we are aiming.

Finally, one American also said (and others agreed) that “another challenge is that we must find ways to protect our command and control against hostile fire.  A degree of physical protection along with a high degree of distribution of command post nodes will be necessary.” Another American added that mobility might not be that important for the higher-level commands (above JTF level), but he agreed that survivability was important, and having an alternate facility or two might also be advisable in case the primary location is damaged.

3. Key Themes and Considerations

Building on the previous discussion about opportunities, challenges, and needs, the following section describes some of these components in more detail and introduces other key themes and considerations debated at the NAC in Tokyo.

3.1 Japan’s Permanent Joint Headquarters (PJHQ)

An overarching theme discussed during the NAC was the need to move beyond an alliance C2 process that relies heavily on a limited number of close personal relationships and develop a more robust institutional process that participants can trust even if they have little to no prior personal connection with each other. A critical variable in this regard is Japan’s stated plan to develop a new PJHQ.

A retired Japanese military officer described Japan’s current SDF overall command structure in peace time as it is established by the SDF Law (see Figure 6). He explained that the Ground SDF is organized into five regional Army commands and a Ground Component Command, which was established in 2018. He added that the roles and responsibilities among the Ground Component Command and the regional commands will have to be clarified in advance of a crisis.  The Maritime SDF is organized into a Self-Defense Fleet with three functional components and five regional Districts. He noted that the Self-Defense Fleet must maintain a stable balance between joint operation requirements from the Joint Staff Office and bilateral operation requirements with the US Navy. The Air SDF is organized by five functional commands with four regional sectors within the Air Defense Command. Air SDF has to consolidate roles and responsibilities of the ADC Commander for ballistic missile defense (BMD) and the commanders for Air Defense Forces of each region to enable effective Integrated Air and Missile Defense (IAMD). Transition to a war fighting command structure can only occur after an order is given by the Minister of Defense and following the use-of-force certification process outlined in Figure 5.

Fig 6. Command Structure of Japan’s SDF[19]

The retired officer went on to describe the current Joint Operation Posture and relationships among Joint Chief, other service Chiefs of Staff, and major command elements, as well as any JTF (see Figure 7). The left side (red line) of the diagram shows Operational Control and the right side (blue line) represents Administrative Control. The arrangement is similar to that of US Forces, and this joint operation posture has been evolving step-by-step since the establishment of the Joint Staff in 2006. The first limited JTF was organized in March 2009 on a temporary basis as JTF-BMD, to respond to North Korea’s announcement of plans to launch a satellite (i.e., carry out a long-range missile test) over Japan’s Tohoku area.[20] In this case, the Air Defense Commander became responsible for ground-based Patriot Units, radar units of the Air SDF, and Maritime SDF Aegis ships. This “temporary” arrangement has been extended several times due to the persistent North Korean missile threat, and it remains active today.

As a Japanese briefer described it, “in this arrangement, the Minister of Defense is supported from a policy perspective by the Ministry’s Internal Bureau and a military expert’s perspective by the Chief of Staff, Joint Staff in a balanced manner like two wheels of a cart.  But it can be said that joint operation of the SDF based on a pre-planned operations plan is a form of centralized control and centralized execution.” He added, “to conduct joint all-domain operations from peacetime through to gray zone and armed conflict, centralized control and de-centralized execution should be pursued. The key point is delegation of authority.” An American offered that the US side, to some degree, will be acting with de-centralized control and de-centralized execution.

Fig 7. SDF Operational System and Roles of the Joint Staff Office and Service Staff Offices[21]

Into this mix comes a statement in the Cabinet-approved National Defense Strategy from late 2022 that “in order to reinforce effectiveness of joint operational posture, Japan will establish a permanent Joint Headquarters [PJHQ] that can unify command of Ground SDF, Maritime SDF, and Air SDF by reviewing the existing organization.”[22] In addition to enhancing jointness, NAC participants highlighted other reasons behind the push for a PJHQ including a desire to streamline the Chief of Staff’s responsibilities so that he is not responsible for both advising the political leadership and overseeing the execution of defense orders (thus also reducing the number of US counterparts he has), and in the process empower the PJHQ commander to be a more effective coalition or combined force partner of the United States. On paper, the position of the PJHQ seems relatively straightforward, to “look down” (as one Japanese participant put it) and make sure Japan’s SDF is prepared and orders are carried out as effectively as possible from an operational perspective, while the Joint Chief “looks up” and supports the political leadership from a policy and military advice perspective to inform those orders (see figure 8). In practical terms, there are a lot of difficult details to work out.

Fig 8. Possible Future JSDF Command Structure[23]

For example, NAC participants based on their own experiences said they expected political and bureaucratic leadership from the Cabinet Secretariat (Kantei), National Security Secretariat, and Defense Ministry’s Internal Bureau to seek information from and provide guidance to the PJHQ directly, complicating the PJHQ’s efforts to simply “look down.” Similarly, in order to calibrate “minimum necessary” levels for the use of force, refine rules of engagement, and support its advice to political leaders, the Joint Staff Office (JSO) will likely reach down into the PJHQ as well. The JSO might also retain overarching responsibilities for intelligence analysis, logistics support, strategic communications, and other SDF-wide activities. In addition, it is possible that the service chiefs will become force providers to the PJHQ, but how that will work (especially if the PJHQ commander is a three-star leader compared to four-star service chiefs) needs to be figured out.

A Japanese participant highlighted the fact that the size of the overall SDF is not increasing, so the PJHQ will need to pull from other, already understaffed, staff offices and regional commands to build up its own staff. Japan’s JSO is already about 8 percent understaffed from its authorized levels, and the overall SDF stood at a 6.6 percent personnel deficit at the end of fiscal year 2021.[24] The situation is not improving, as Japan’s SDF reportedly missed its recruiting target by more than half in fiscal 2022.[25]

The final size, scope, and location for the PJHQ had not been announced by the time of NAC Tokyo, although some of these questions are likely to be answered by the summer or fall of 2023 as the Defense Ministry begins budget preparations for next fiscal year. It is up to Japan to decide how to divide the roles and responsibilities between the JSO and the PJHQ, how to allocate manpower, and other details, but US and alliance interests are intricately intertwined in these decisions, and US policy makers are looking for the proper time and manner to engage Japanese counterparts on the details. It will be much easier to “design in” some US-Japan connectivity with the PJHQ at an early stage of its development, rather than wait until after it is fully stood up. As one US military officer explained, “we need to see the general structure from Japan first, and then we can move with them in a close bilateral way.” Another question as yet unanswered for the PJHQ is what will be its responsibility in terms of battlespace or geographic reach. One US participant asked if the South China Sea would be included, for example, “or what about the Philippines?”

As for the roles and responsibilities for the PJHQ, some Japanese participants laid out what they saw as most likely for the various phases and scenarios.

Likely PJHQ Roles during Peacetime:

  • Formulation of joint defense plans
  • Formulation of bilateral plans with US representatives of the Bilateral Planning Committee[26]
  • Operational control over major commands
  • Planning and execution of joint/bilat/multilateral training and exercises
  • Peacetime engagement with relevant organizations (e.g., National Police, Coast Guard, etc.)
  • Humanitarian assistance and disaster relief operations

In Gray-Zone Situations:

  • Situational awareness of ongoing situations
  • Formulation of action plans during indications and warning (I&W) situations
  • Coordination of flexible deterrence options (FDOs) with INDOPACOM
  • Execution of Defense Minister’s orders as approved by the Cabinet/Diet

In Armed Attack Situations:

  • Same as gray-zone situations
  • All domain bilateral coordination (especially ISR and targeting)

Another Japanese participant noted that a key challenge for the SDF is to establish a PJHQ while developing a concept of operations for constantly evolving threats and to establish a command structure for IAMD that fully utilizes new counterstrike capabilities.  He added that the SDF’s Command, Control, Communications, Computers (C4) Intelligence, Surveillance and Reconnaissance (ISR) network of the SDF must be integrated to ensure interoperability among all services and have sufficient interoperability with the US network. It should be redundant to sustain its function 24/7 and resilient against kinetic attacks and non-kinetic disruption including cyber-attacks. These are ambitious but important goals.

Most participants recommended that the Japanese government should try to create a “fully grown” or fully empowered PJHQ from the start, rather than build it up incrementally over time. They felt that this would be the best way to maximize the PJHQ’s chances for success, but a few feared that Japanese policy makers might opt for a “start small” approach. One retired US military officer thought that one thing the PJHQ could do would be to anticipate the need for some of its own JTFs and “get them on the board” in terms of planning and preparation.

In terms of the ideal location for the PJHQ, participants were divided. Some thought that it should be located close to the center of gravity for political decision making (i.e., in Ichigaya essentially co-located with the JSO and Ministry of Defense). As one Japanese participant said, “the Prime Minister will eventually want to approve certain actions, timing, and targets.” Locating in Ichigaya would fit well with an incremental approach and give the Chief of Staff good visibility into how the delineation of roles and responsibilities between the JSO and PJHQ is working out (and settle disagreements quickly).

Others, however, thought that this arrangement (in Ichigaya) could effectively overshadow and weaken the PJHQ, stifling its authority and operational effectiveness. Others emphasized the potential benefit of positioning the PJHQ closer to where conflict is most likely to erupt (i.e., where orders will be carried out), while others expressed concern about vulnerability to enemy attack in that case. Most participants suggested that the PJHQ should have an ability to “plug into” or “bolt on” a US C2 component or otherwise effectively create a co-located bilateral C2 capability.

A Japanese participant described the PJHQ as “the operational counterpart of INDOPACOM, and to a lesser extent a strategic counterpart as well,” with the JSO perhaps remaining as the primary “strategic counterpart” for INDOPACOM (see Figure 9). While most participants accepted this general premise during peacetime, the details surrounding how this would be realized sparked a lot of debate. The image for some is that PJHQ would act something like a defense-of-Japan/regional security combatant command for Japan, but in the case of a significant Japan or regional military crisis, INDOPACOM would almost certainly designate a JTF to handle discrete theaters or missions. “The real bilateral gap,” as one US military officer described it, “is at the JTF level,” and he suggested that the PJHQ would be the right counterpart for a US JTF focused on Japan.

Fig 9. Possible Relationship between PJHQ and US Forces[27]

It is also possible that INDOPACOM will develop some type of warfighting Joint Force Headquarters in the region in the near future, as the 2023 National Defense Authorization Act instructs INDOPACOM to do by October 2024.[28] There is precedent for this approach in PACFLEET’s JTF-519 that was focused on regional contingencies and active for about a decade until it was disestablished in 2013.[29] A retired US military officer described the Joint Forces Headquarters concept as an O-6 level or below “warfighting club that plugs into” INDOPACOM or some higher-level JTF, so “it is very different than the PJHQ in that it doesn’t have a commander in charge” and might plug-into the PACFLEET Commander’s staff or USARPAC Commander’s staff depending on the command structure involved. JTF-519 was standing and distributed, with a core of 150 personnel that could expand to 400 (to fit within command ship berthing limits).[30] The PACFLEET commander was commander of JTF-519, and elements of that JTF were activated in 2011 to augment USFJ to for the Joint Support Force for OPERATION TOMODACHI.

If a regional crisis becomes broader than one narrow conflict and involves multiple theaters or distinct missions, then it is likely that Japan will be involved in some INDOPACOM activities but not others. It is also possible that INDOPACOM would create two, three, or more JTFs to help manage this fight, directed either from INDOPACOM in Hawaii or possibly by a new Joint Force Headquarters located in Hawaii or Guam. In this case, the PJHQ counterpart would almost certainly be INDOPACOM’s JTF-Japan (not INDOPACOM directly), and this bilateral command could plan and oversee both US support for the defense of Japan and Japan’s (Diet-approved) contributions to INDOPACOM’s regional security actions. These options are discussed in more detail in section 4 of this summary report.

3.2 Defense of Japan versus Regional Contingency

A frequent topic of discussion among NAC participants was how to tailor alliance C2 modernization to different types of scenarios that would benefit from closer integration of decision making and application of both countries’ military assets. For both legal and political reasons, Japan’s ability to partner with US forces will be restricted for a regional contingency, or what Article 4 of the US-Japan Security Treaty describes as a time when “the security of Japan or international peace and security in the Far East is threatened.” However, there will be far fewer restrictions in a defense-of-Japan situation, or what Article 5 describes as “an armed attack against either Party [i.e., Japan or US forces] in the territories under the administration of Japan.” In this case, through the Treaty each country commits to “act to meet the common danger in accordance with its constitutional provisions and processes.”

As introduced in section 2.2, Japan’s SDF can only use force in two different situations when approved by Japan’s Diet: 1) an “Armed Attack Situation” against Japan, or 2) a regional contingency involving an attack against a country that is in a close relationship with Japan that also represents a “Survival Threatening Situation” for Japan.[31] There are relatively strict limitations in both cases regarding SDF deployment flexibility and rules of engagement, depending on the situation, but Japan’s SDF would be fully engaged in these cases.[32] This should allow the allies to make full use of a more integrated and modernized C2 framework.

Separately, some US-Japan military integration is possible in a third situation that is less immediately threatening to Japan, but when the US is engaged in “situations that will have an important influence on Japan’s peace and security.” This law covers support for US actions “contributing to the achievement of the objectives of the Japan-US Security Treaty,” or presumably Article 4 conditions.[33] It could reflect some kind of gray-zone situation or even a limited conflict involving the US and North Korea, for example, or the US and China in the East China Sea. In those cases, Japan’s involvement would be restricted to logistics support activities, search and rescue activities, ship inspection operations, and some “other measures” related to Japan’s security.[34] Moreover, Japan’s support needs to avoid any area of combat or dangerous circumstance, and it should avoid having its support become integrated with America’s use of force (which the Japanese government believes is demonstrated by not providing support at “the scene where combat activities are actually being conducted”).[35]

In addition, there are some types of alliance joint military action that can occur during peacetime, such as so-called Article 95-2 missions.[36] This refers to an article of Japan’s SDF Law that allows SDF personnel to protect US weapons and other equipment that are engaged in activities contributing to Japan’s defense (also referred to as “asset protection” missions). Examples of US activities that would qualify under Article 95-2 include ISR missions (including ballistic missile alert ISR), transportation and replenishment under the “Important Influence Situation,” and bilateral or multilateral exercises that enhance the ability to defend Japan. In 2021, Japan’s SDF helped protect US military assets four times during ISR activities and seventeen times during exercises.[37] The pace increased to 27 total missions in 2022, according to comments by a US military officer at the NAC.

Asset protection missions are an interesting example of alliance C2 because they are a relatively recent activity (only allowed since around 2017), and they simulate the kind of back-and-forth that starts with an expressed desired outcome by one side and then adds practical but politically acceptable planning, followed by well-coordinated execution. The process of asset protection missions is closely coordinated between the governments. For missions with a sufficient lead time, the system works relatively well, but it seems clear that this kind of process would not be adequate for integrated missions during wartime. It also highlights the benefits of co-location (either in Japan or via liaison officers) in terms of speeding up the process and generating a high success rate.

The most sophisticated and streamlined example of current alliance connectivity is probably missile defense, as Japan has been receiving Shared Early Warning data since the late 1990s. They also share intelligence gathered by assets including missile defense radar systems (TPY-2 radar) and US and Japanese Aegis-equipped destroyers.[38] This mission is characterized by high levels of alliance interoperability and frequent bilateral training, as well as solid jointness on the Japan side (with its BMD JTF). But even here there are gaps in how each side delegates authorities. One US official at the NAC said that the US often delegates missile shoot-down authority to the Captain (O-3) level, whereas in Japan the Prime Minister can sometimes be involved.

Also, with greater closeness often comes higher expectations of a partner, and alliance missile defense cooperation has created some friction in the past that should be kept in mind. A retired Japanese military officer at the NAC recalled, “since the Clinton administration I’ve been told that our joint missile watches of North Korea can be politically sensitive in Washington. There has been no specific agreement on joint Japan-US cooperation, and each country has operated its forces on a national tasking basis. As a result, the allies occasionally can have a different sense of urgency regarding a North Korea missile launch, and when the situation in the South China Sea became tense, for example, there was a difference in the order of their priorities. This made the allies uneasy in the allocation of their BMD assets.”

Overall, NAC participants expected that modernized alliance C2 will have to be flexible to accommodate this “sliding scale” of Japanese participation in allied military activities. Figure 10 summarizes the permissible SDF roles and missions under different circumstances, and not surprisingly these expand greatly as the direct threat to Japan becomes more acute. There would be relatively few limitations on potential alliance military activity in a defense-of-Japan (or armed attack) situation, but a lot more in a broader regional contingency. In areas of ISR, missile defense, logistical support, and even asset protection, there is an increasing operational tempo of integrated alliance activity. These would benefit immediately from enhanced alliance C2 and bilateral planning capacity, while more dangerous or destructive alliance actions would only come into play in special dire circumstances. Still, preparing for these scenarios and being able to transition to more tightly knit C2 structures are necessary.

A retired Japanese military officer highlighted this last point about a regional contingency, which could easily begin from a Japan perspective as an “Important Influence Situation” and then transition to a “Survival Threatening Situation” and even an “Armed Attack Situation.” In this sense, the “defense of Japan” can be so closely related to a regional contingency that we really need to consider this as an alliance in advance and develop a common understanding of the connections and the C2 transitions. “The defense of Japan is not a stand-alone issue here,” he said, “so they cannot be independent of each other.”

A US military officer agreed, clarifying that the purpose of a US JTF Japan (if created) likely would be to deliver effects in support of the US (INDOPACOM) effort. Part of that effort in a regional contingency could be to coordinate with Japan on its support role in an “Important Influence Situation” or a “Survival Threatening Situation,” but then it could also become coordinating US support for Japan’s defense as one of several INDOPACOM missions during a wider conflict. From a US perspective, it becomes a matter of aligning the defense of Japan actions with other INDPACOM actions to have maximum effect on the adversary and reduce the threat to the allies collectively.

Fig. 10.  Outline of Permissible SDF Roles and Missions Under Different Circumstance[39]

* = Overall, alliance peacetime security coordination includes (according to the 2015 Defense Guidelines) ISR, air and missile defense, maritime security, asset protection, training and exercises, and logistic support (all carried out in a national tasking manner based on domestic laws and civilian political decision making).

Separately, a retired US government official noted that in a contingency scenario, even though it is possible or even likely that the adversary will make the mistake of striking Japan directly and expanding its involvement, we cannot assume that. “The C2 structure we devise will need to be flexible enough and close enough to deal with potentially big differences in how we are responding to a regional crisis in real time to minimize political conflict or misunderstanding among the US and Japan.” In addition, a Japanese government official noted that the Japanese public needs to be considered and provided information to help “catch up” to where the Japanese government is on the issue of support for a regional contingency. He said that the Japanese government “will face difficult issues related to the allocation of resources to the defense of Japan and support for US regional operations,” and it will need public support.

A retired US military officer said that one important question related to this topic is what will be the primary mission of the PJHQ. “Will it be to defend Japan? If so, that is not the primary mission of INDOPACOM, which has a much wider set of responsibilities.” Other participants agreed that the allies will need to think carefully about aligning missions within the new C2 framework, so close C2 partners have similar missions. “A command is shaped by its missions, functions, and tasks,” said the retired officer, “and then the tasks are often divided up among JTFs.” These missions, functions, and tasks in turn shape the military’s job to “man, train, and equip” its forces. Japan’s JSO will likely retain the “man, train, and equip,” role (together with its service components), and depending on the PJHQ’s responsibilities (related to “missions, functions, and tasks”), it could acquire missions that will overlap well with parts of INDOPACOM or some new US JTF, possibly based in Japan. Other PJHQ missions might not overlap well.

A related issue is battlespace. Where do we expect US and Japanese forces to operate? A Japanese participant reminded the group that the 2015 US-Japan Defense Guidelines explicitly refrains from defining a geographic scope for addressing situations that endanger Japan and the alliance.[40] “But,” he added, “to execute Japan’s mission effectively, there should be some geographic limitation or designated domains.” Politically and operationally, it will be difficult for the SDF to be active too far afield during a crisis. A retired US military officer concurred, emphasizing that the allies should avoid sharing battlespace. “You can’t have two forces with separate commanders fighting in the same battlespace,” he said, arguing that to do so would risk friendly fire incidents or sub-optimizing weapons systems and other shortcomings. The allies have done this before in disaster relief operations (e.g., during the response to Super Typhoon Haiyan in late 2013) and even exchanged officers between command ships, but many participants felt that a war fight would be different.

3.3 Information Sharing and Cybersecurity

NAC participants frequently highlighted the need for a high degree of shared situational awareness for any C2 modernization. As noted in section 2.1, OPERATION TOMODACHI revealed both strengths and weaknesses in terms of information sharing and developing a common view of the priorities and risks when deciding on next steps. A US military officer at the NAC suggested that this info sharing effort should go up to the highest levels in both governments when there is a severe crisis that demands an alliance response. In his view, alliance C2 modernization should include an opportunity for joint briefings of the US president and Japanese prime minister (i.e., National Command Authority or NCA) by military personnel from both countries. “There should be provision for joint briefings by the INDOPACOM Commander and Japan’s Chief of Staff for the two countries’ defense leaders and even the NCA, when appropriate.” Otherwise, he commented, the top leaders’ understanding of a dynamic situation and the implication of various options could diverge in small but meaningful ways.

In addition to high-end strategic information sharing among top leadership, NAC participants also discussed lower levels of day-to-day ISR connectivity, joint and bilateral interoperable communications, and equivalent information security practices that are the underlying enablers of a modernized C2 structure. US participants recognized Japan’s recent advances in terms of better jointness and information security compared to the past, but some on the US side said that it is still not at an adequate level to share detailed plans. “Cybersecurity and information sharing is the main limitation we have,” according to one US military officer, “and without it we can’t do the bilateral coordination that we need to do.”

Part of this American concern about cybersecurity stems as much from an overall sense of alliance vulnerability as it does from specific concerns about Japan. For example, US officials have identified China as probably “the broadest, most active, and persistent threat to the US government and private-sector networks.[41] Soon after this testimony, Microsoft Corporation and the cybersecurity agencies of the United States and its “Five Eyes” partners issued a warning based on their discovery of Chinese state-sponsored (Volt Typhoon) infiltration onto critical infrastructure networks on Guam and other places, presumably planting “sleeper” malware that could be used to disrupt allied activity during a regional crisis response.[42] The extent of this infiltration is not yet clear, but concern about these kinds of threats has prompted the US Defense Department to spend up to $2 billion on “zero-trust” protections, while the services are each spending roughly an additional $2 billion over a 5-year period in this area.[43]

Japan was notably absent from the Five Eyes-issued infiltration warning about Volt Typhoon, and Japan apparently only received a brief “heads up” about the announcement just minutes before it was released.[44] In part to reduce this gap in partnering ability, Japan’s 2022 National Security Strategy prioritizes new cybersecurity investments and a major restructuring of its National center for Incident readiness and Strategy for Cybersecurity (NISC). Draft legislation to guide this restructuring is currently being discussed and could be submitted to the Diet by 2024. In the meantime, Japan’s Defense Buildup Program earmarks about $7.5 billion for cybersecurity over the 5-year span, so the resources should be there on the Japan side to complement US investments. The problem is the scale and complexity of the threat. The allies should look for ways to enhance partnering on cybersecurity so that they can share more information at earlier stages of detection, and the drafting of Japan’s new cybersecurity legislation is a good opportunity to explore.

There appears to be interest on both sides in this regard. For example, rather than simply repeat complaints that Japan’s investments and reforms are not yet good enough in general terms, there is apparently a bilateral effort underway to tackle specific areas of information sharing and make enough progress in some compartments to share detailed information and “show Japan what ‘winning’ looks like,” with the goal of stimulating additional reforms in other areas.[45] That fact that this push coincides with Japan’s own increase in cybersecurity and C2 investments as part of its new Defense Buildup Program gives the allies a good opportunity to make additional progress.

Another way to enhance information sharing and facilitate communications would be to expand the inclusion of liaison officers (LNOs) in each other’s commands and units, although the allies already have a relatively robust liaison officer program. One US NAC participant said that “LNOs are great, but that’s not what’s needed here.” He noted that at US Army Pacific Command (USARPAC) in Hawaii the deputy commander is an Australian, and he suggested that the US and Japan could consider adding “senior Japanese officers in leadership positions at USARPAC and perhaps even at PACLEET” to improve interoperability and communications. Another US participant, however, pointed out that the US military’s frequent use of “NOFORN” (not releasable to foreign nationals) designation for certain classified information can often complicate work for these foreign exchange officers. That is sometimes a US-side limitation, although it can also be due to the involvement of “other country information” that the US is not explicitly authorized to share with a different partner. For this reason, one US participant suggested creating a multilateral information sharing framework (particularly with Australia, the UK, Japan, and South Korea) that focuses on the topics most pertinent to a regional contingency. If the allies want to pursue the idea of Japanese foreign exchange officers, doing so in the area of logistics might be a good place to start to avoid legal and political sensitivities in Japan about the use of force, as well as to reduce information sharing hurdles.

Japanese and American participants alike recognized that the topic of information sharing is vast and covers everything from top leaders’ briefings all the way down to “that firing battery on Yonaguni Island, to make sure they have the information they need to have a more efficient kill-chain and that they know what they are shooting at.” A US participant emphasized one big hurdle we face is that “an awful lot of US planning is transitioned to JWICS (Joint Worldwide Intelligence Communications System),” and JWICS is not going to be accessible in an alliance context “no matter what the C2 structure is.” “But,” he continued, “the PJHQ could be the key to overcoming this hurdle, because that can be the primary alliance connection point to integrate intellectually with INDOPACOM” via a US JTF-Japan commander.

3.4 Bilateral versus Minilateral Connectivity

Another theme discussed at various times during the NAC was the extent to which alliance C2 modernization should be designed to accommodate the involvement other national partners from the beginning. “If we are talking about some kind of Taiwan crisis that sparks a broader conflict with China [for the US],” one American participant offered, “I don’t think we can fight China by ourselves, which suggests to me that a China fight will be a coalition fight.” “So,” he asked, “how do we build the on-ramps for others so it’s not ad hoc, but it doesn’t slow us down either?”  Similar questions were raised at other points in the dialogue, and one participant suggested that there could be useful lessons from the International Security Assistance Force in Afghanistan or the US-led coalition in Iraq.

On this latter point, a retired US military officer did not think Afghanistan or Iraq would be useful because “it was a totally different kind of war fight.” He added, “those arrangements with other partners were full of caveats and varying rules of engagement, but it was sufficient in a situation where we had total air superiority and control over a wide range of important variables. That won’t be the situation we face in East Asia.” He agreed that the US could not handle this alone, but argued that “it will need to be more of a ‘combined together,’ rather than a ‘coalition together’,” meaning a combination of close US bilateral partnerships with allies rather than one big coalition. Another retired US military officer with experience in those theaters, however, encouraged the group to think more about what different partners can contribute rather than what they cannot do. He recalled other countries’ units in Iraq and Afghanistan that had much stricter rules of engagement than US forces did, but there were still a variety of important tasks to which they could contribute.

Participants did note that the situation could be different between a China-related scenario and a North Korea contingency. In the North Korean case, a multilateral framework already exists to accommodate contributions by various allied and partner nations. This is the United Nations Command (UNC) structure that moved headquarters from Japan to South Korea in 1957 and left behind seven designated “UN-flagged” bases in Japan that make up UNC-Rear, in case there was ever a need to confront North Korea again as a UN-authorized multilateral coalition.[46] Eleven countries are signatories to this agreement including the US, Japan, Australia, the UK, Canada, the Philippines, France, and others. Still, there are a variety of important questions to consider about the possible C2 interactions among INDOPACOM, US Forces Korea, USFJ, and Japan’s PJHQ.

Separately, multiple nations have been cooperating since 2018 to help enforce UN sanctions against North Korea levied under UN Security Council resolutions 2375 and 2397 by creating a cooperative surveillance and interdiction scheme that uses the USS Blue Ridge based in Japan as a hub for analysis and communication. This “Enforcement Coordination Cell” coordinates the collection and fusion of information on violations of the above-mentioned UN sanctions, drawing on data collected by the ships, planes and other surveillance platforms and mechanisms in a coalition that includes the US, Japan, France, South Korea, Australia, Canada, New Zealand, and the UK.[47] There is no similar experience on China-related matters, and even though Japan did approve Reciprocal Access Agreements with Australia and the UK in April 2023, these agreements were not designed with multilateral connectivity in mind.[48]

4. Three Basic Options for Alliance C2 Modernization

Generally speaking, most NAC participants expected that alliance C2 modernization would move in the direction of a bilateral command, rather than a unified command or a combined command with a single commander. The current US-Japan Defense Guidelines reflect this, stating that “the Self-Defense Forces and the United States Armed Forces, in close cooperation and coordination, will take action through their respective chains-of-command.”[49] Japan’s legal system and political dynamic supports this conclusion as well. As one retired Japanese SDF officer elaborated, “all activity by Japan’s SDF including joint operations with US forces are to be conducted under Japanese independent judgement, and in accordance with the Constitution and domestic law…that’s the official line. So, the Japanese government does not want a unified command or operation. But, many recognize that Japan and the US might not be able to deal with adversaries unless we can work more closely and exercise the synergy effect in military operations. We need to unify thinking, planning, and operation, even if there is some separation in our C2 structure.”

This retired officer proposed the image of the letter “Y” as an example, where the top left and right of the letter “Y” represent bilateral leadership, but they funnel down into singular action (i.e., unity of effort, if not unity of command). Some NAC participants thought that a more closely integrated or combined approach at the top would still be necessary, but virtually all agreed that a US-Korea-style Combined Forces Command with a single commander and an “integrated staff” (i.e., a staff in which one officer only is appointed to each post, irrespective of nationality and Service) would not suit the US-Japan alliance.

The “Y” approach could allow for a bilateral command structure, but to be effective the allies will need to improve their processes for decision making and information sharing at the top ends of the “Y”, as well as to create a C2 node at the junction of those commands that has sufficiently similar authorities and capacity on down to the bottom of the “Y”. The higher up that node can be established, the better, but it doesn’t help much if there are mis-matched delegated authorities below it (i.e., if US forces can move forward based on a bilateral command decision, but Japan’s SDF has to keep going back up the chain of command to get approval for various discrete actions). Operational control over national forces would likely remain with each country, although the group did not rule out the possibility that tactical control could shift depending on the mission and location of the task.

The following three basic options describe the gist of various ideas floated by NAC participants over the course of three days. These do not represent an exhaustive list of the options available to the allies, and the NAC did not try to make specific recommendations.

4.1 Building Blocks

One option for the allies is a relatively simple and incremental approach that builds upon the many improvements that have been made in alliance security cooperation over the past decade or two. After all, the allies only concluded a General Security of Military Information Agreement (GSOMIA) in 2007, so that they could more easily share classified military information.[50] The ACM and related mechanisms for bilateral planning and operations coordination date back only to around 2016, and the Bilateral Information Analysis Cell (BIAC) is less than a year old. Combined asset protection missions are growing in frequency and complexity, so this is an alliance “muscle” that is being flexed and tested more frequently in just the past few years. All of this presents opportunities to piece together a more coherent and connected set of current activities that can add up to qualitatively improved alliance C2 process.

Part of this effort would require more frequent and persistent co-location of US and Japanese personnel. NAC participants described facilities at Yokota Air Base and Japan’s SDF headquarters at Ichigaya that are used intermittently during exercises and available for a crisis, where alliance officers and officials can come together to do planning or coordinate operations. As Japan prepares to stand up its PJHQ—either at Ichigaya or at some other location—the allies have an opportunity to build out some of this space and staff it bilaterally on a more consistent basis. This could potentially include the embedding of US military personnel responsible for missile defense within the PJHQ, if Japan’s Air Defense Command comes under its purview, to allow for regular deconfliction of BMD activities. Other non-offensive areas of security cooperation could be candidates for closer C2 integration in the near term, and NAC participants mentioned logistics and intelligence/information sharing specifically in this regard. Could the BIAC, for example, be expanded to become more of a bilateral Joint Intelligence Operations Center in the near future?

Of course, these kinds of qualitative changes to how current forums and frameworks are leveraged will be difficult to do without some staffing and procedural adjustments at USFJ, as well as between USFJ, INDOPACOM, and relevant Component Commands. It might be possible to add some staff to USFJ seconded from various Component Commands that would help provide this additional manpower on the US side. This could be accompanied by some delegation of authority to these bilateral or combined units that will allow certain decision making, planning, and execution to take place within Japan in a bilateral way.

Movement in this direction would not necessarily create a new form of alliance C2, and some NAC participants pointed out that the ACM, for example, is a “forum that bridges two separate C2 structures…it is not C2.” Still, several participants recommended upgrades to the current ACM to improve its functionality. These included suggestions to clarify the role for higher level military and bureaucratic representation on the ACM (above the Director General/Assistant Secretary level), to involve a wider range of relevant government stakeholders as standing members (e.g., Police, Coast Guard, critical infrastructure-related, etc.), and to assign a Japanese Cabinet-level political representative to the ACM so that the framework is better prepared to facilitate high-level political decision making. A US participant suggested that an augmented ACM involving more government partners in Japan and senior policy makers could be exercised in a way similar to four-day crisis management drills conducted annually by the United States and South Korea.

If the allies do move forward in an incremental fashion by modernizing alliance C2 components to address near-term priorities, it is still beneficial to think strategically about long-term goals and how short-term steps can support those objectives. In other words, even if we are approaching this in a piecemeal fashion, the allies will benefit from a shared understanding of how these pieces fit into a larger picture, as well as how the building blocks could support more robust alliance C2 in the future.

Part of this could be the anticipation of a region-wide crisis and pre-designation of a US component commander (probably PACFLEET) as a lead JTF, and to build US-Japan connections between key players in advance. In connection with this, one retired US military officer recommended that whichever component command is pre-designated, an effort should be made to staff that command in more of a joint way during peacetime, so that any transition to crisis mode would be more seamless and allow for alliance relationship building over a long period of time with the proper offices. Conversely, if a future US counterpart for Japan’s PJHQ is more likely to be a reconfigured and more operationally empowered USFJ (rather than a new JTF “bolted on”), then incremental augmentation of USFJ might be a better way to go.

During the NAC, a retired Japanese SDF officer prepared a matrix for the group that lays out some of the important considerations as we debate C2 modernization (see Figure 11). The overall theme of the slide was positing how much to anchor alliance C2 changes within the context of the 2015 bilateral defense guidelines. One question, for example, is whether alliance C2 can or should incorporate the ACM’s BOCC and CCCs, which are directly related to military operations. If the ACM is elevated politically to focus more on military-informed decision making passed up to the Cabinet level (e.g., NSC-NSC), for example, then the BOCC and CCCs might be carved out and reconnected to the PJHQ and a US counterpart in some way. PJHQ-assigned personnel could also serve as LNOs at INDOPACOM. On the issue of “time coverage,” he offered the opinion that reinforcing alliance responsiveness is one key to support deterrence regarding a Taiwan crisis, so a 24/7 aspect to it would likely be important.

Fig. 11.  Issues to Consider for Alliance C2 Modernization[51]

The “Issues to Consider” slide at the bottom refers to historical, legal, and political factors that will influence how these questions get addressed.  As one US military official noted, the operational coordination within the alliance already works relatively well, and for major exercises or designing flexible deterrent options (FDOs), for example, “on the military side we [US and Japan] are able to sort out the plan pretty quickly.” “But,” he added, “what we find when we start to move forward is that the political coordination takes longer than expected or we have to scale back our plans short of something that we thought would be necessary.” This comment reflects a positive alliance dynamic of already close communication and coordination among US and Japanese military personnel based in Japan, but it is not sufficiently connected to (or directed by) the political level in a bilateral way. Participants did not think this would be sufficient in a wartime situation, and one US participant suggested that greater exercising of political decision making during military exercises should be a near-term priority.

The “Issues to Consider” slide did not refer to information sharing specifically, but one US official noted that information security and cyber/network security are such critical enablers for a multitude of important building blocks that the allies should not wait to make progress on this front. “The structure is one piece that we will work on over time,” the official said, “but cybersecurity is so fundamental that we can press on this enabling factor now.”

An American participant called attention to the fact that technology decisions each partner is making now could either facilitate or complicate alliance C2 modernization, depending on the choices they make. He mentioned Japan’s near-term decisions looming for cybersecurity upgrades and its counterstrike system (including sensor network and C2 upgrades), while the US confirmed in March 2022 its implementation plan for a new Joint All-Domain Command and Control (JADC2) to “‘sense,’ ‘make sense,’ and ‘act’ on information across the battlespace quickly using automation, artificial intelligence, predictive analytics, and machine learning,” which will unfold over the next several years.[52] Alliance dialogue and action on C2 modernization must keep these evolving technology trends in mind in real time as the engagement unfolds.

Separately, but consistent with this theme of closer integration, one former US military officer at the NAC made a strong appeal for more joint shared use of bases in Okinawa. “Japan’s Amphibious Rapid Deployable Brigade (ARDB) should be at Camp Schwab with our 31st Marine Expeditionary Unit (MEU) learning from one another, using the same equipment…and Air SDF pilots at Naha Airport should be working more closely with US pilots at Kadena Air Force Base, sharing best practices and flying the same profiles.” “The way we integrate our forces at bases outside of Okinawa is the future of the alliance,” he said, “but the way we remain separated in Okinawa is the past, and that’s not what the local citizens should see.”

Sticking with bases in Japan, it is likely that the protection of bases will become a more frequent and substantive area of alliance coordination in the future. If the allies become more integrated in terms of how they develop and execute missions around Japan, then they will have to consider the “tooth-to-tail” spectrum of how missions are carried out and supported, including base protection. As one US participant noted, “if a base is attacked in Japan and Americans die, we can’t just say it was Japan’s job to protect it. It’s a shared responsibility.”

4.2 Bilateral Staff Approach with JTF-Japan

Adopting a “building blocks” approach involving incremental improvements to Alliance security coordination can be an end in itself, or it can be a steppingstone toward a more formal and robust bilateral C2 relationship. Most NAC participants expressed support for the latter, believing that a more comprehensive side-by-side arrangement would be necessary to productively leverage alliance assets and deal with evolving threats. The NAC did not consider specific C2 modernization proposals, but two types of possible arrangements emerged from the discussion. There could be numerous variations, but for the sake of clarifying the differences between the two main types, the author prepared two conceptual organization charts for consideration (see Figures 12 and 13). The first, addressed in this section, features a permanent bilateral joint staff based in Japan that would focus on preparing the allies to fight together in a variety of threat scenarios and across all domains. It would be accompanied by the introduction of a new US JTF-Japan (or “Joint Force Japan”), which could either be attached to USFJ roughly as it exists today, or it could become an integral part of a reconfigured USFJ.

Fig. 12.  Possible Arrangement for a Bilateral Joint Staff Office in Japan[53]

NAC participants generally thought that a new bilateral joint staff office would need to be accompanied by a new US standing JTF in Japan, connected to USFJ in some manner. This JTF-Japan would be led by a US military officer solely dedicated to this mission, probably supported by a small core staff co-located with USFJ, but with the bulk of his/her team working at a new standing bilateral staff office. The Japan-side of the bilateral staff office would likely be dispatched from Japan’s PJHQ and report directly there. In this sense, the bilateral joint staff office is designed to serve Japan’s PJHQ and the US JTF-Japan concurrently, and it likely be co-led by a representative from each country at an equivalent rank.

A bilateral joint staff office could become the primary forum for bilateral information sharing, intel tasking and analysis, bilateral planning, facilitating BMD operations coordination, logistical support coordination, asset protection mission coordination, counterstrike coordination, and other functions, and it would be tested and tempered through regular bilateral exercises. One US military officer thought that an important function during conflict would be to maximize compatibility between US operational plans and whatever Basic Action Plan was being prepared for Japan’s Diet to approve. For information sharing, a “mission partner environment” could possibly be created, building upon recent improvements in this area by INDOPACOM.[54]

The bilateral joint staff office would probably not have any forces assigned to it, and it would not be in command of anything. Those authorities would likely remain with the PJHQ for Japan’s SDF and with JTF-Japan/USFJ and INDOPACOM for US forces. It is conceivable that INDOPACOM might assign some US forces to JTF-Japan as/when needed, so that certain operational control coordination between the PJHQ and JTF-Japan could take place in one place and by personnel who know each other well. This would be useful if there was some kind of surprise incident locally that required US forces in Japan to respond quickly with what was available in-country (i.e., part of “reinforcing alliance responsiveness” mentioned earlier). If the crisis persists and JTF-Japan needs to be augmented, it can carry on with much of the original core team intact, so it does not have to “hand-off” the alliance coordination work to an entirely new team coming in from out of country, as was largely the case during OPERATION TOMODACHI.

The future of the ACM under a bilateral joint staff approach is unclear. It seems logical to relocate the BOCC and CCC functions within the new bilateral joint staff, and the ACM could simply carry on as a combination of the Joint Committee (for issues related to the Japan-US Status of Forces Agreement or SOFA) and the Alliance Coordination Group (for policy coordination of a wide range of remaining defense cooperation issues). The linkage between the ACG and the bilateral joint staff would be tight, to address many of the political decision-making challenges referenced earlier, but whether or not the ACG could formally “approve” bilateral joint staff office plans or proposed movement of forces is an outstanding question. Surely, the ACG would be a useful tool for clarifying operational boundaries and maybe clearing some political hurdles to get the most out of alliance security cooperation, but the authority to approve plans, exercises, and force movements would probably still rest in traditional (and national) hands.

The bilateral Security Consultative Committee that brings together the defense and foreign policy ministers/secretaries from both countries (the so-called 2+2) would continue to function in this scenario and sits high above the bilateral joint staff office. It is not represented in Figure 12 because it is the process that informs decision making by the national command authorities, and from there Japan’s Minister of Defense and US Secretary of Defense issue orders through their respective chains of command. In this way, the traditional alliance management process does not change much, but it would gain a powerful new tool in the form of the Bilateral Staff Office.

An outstanding question is what kind of relationship should be fostered between the PJHQ commander and the INDOPACOM commander. Clearly, a close relationship is desired, as both are the operational leaders for their forces carrying out missions in the region. The JTF-Japan commander would be the INDOPACOM commander’s chief operational representative in Japan, essentially managing all of the day-to-day interaction between the PJHQ and INDOPACOM, but the PJHQ commander would also likely have occasional strategic consultations with the INDOPACOM commander directly, either together with or independent from Japan’s Chief of Staff, Joint Staff. Depending on how the JTF-Japan is established, it might be possible to consider it as a kind of “INDOPACOM Forward,” making that PJHQ-INDOPACOM connection even more explicit. One Japanese participant asked if a US JTF-Japan could be conceived of more ambitiously as a JTF-Northeast Asia based in Japan (i.e., encompassing US Forces Korea), but the group overall did not pursue this idea further.

Another question is what rank the JTF-Japan commander should be and whether or not the JTF-Japan command should be augmented during a major crisis with a higher-ranking officer. For example, the workload and responsibilities for the JTF-Japan commander during peacetime might suggest a level of one-star or two-star leadership, with an O-6 level lead seconded to the Bilateral Staff Office. But in the event of a major security crisis, the allies could raise the level of this arrangement in a similar way to OPERATION TOMODACHI. In this case, the JTF-Japan commander might move into the Bilateral Staff Office to lead for the US side, and a newly designated JTF-Commander could shift from Hawaii to Japan (e.g., a 3-star or 4-star officer, possibly even the PACLFEET commander, who led the Joint Support Force in OPERATION TOMODACHI in 2010 with activated elements of US JTF-519). In this way, a more authoritative US JTF-Japan can “fall in” on the Bilateral Staff Office framework and more quickly and fully empowered to perform with Japan-based US military assets. Another possibility could be to strengthen USFJ’s operational capacity and name the USFJ Commander to lead all US activity in Japan as a sub-unified command under INDOPACOM.

4.3 Bilateral Command Approach with JTF-Japan

A higher level of alliance C2 modernization could involve creation of a standing bilateral JTF in Japan that could play a more direct role in carrying out certain defense missions that benefit from high levels of alliance integration and interoperability. The list of command functions would be very similar to the one mentioned previously for coordination at the bilateral staff office, but instead of simply informing and coordinating the plans for action by others, the Bilateral Joint Task Force could potentially have US and Japanese forces assigned to it. As a bilateral command, there would not be one single commander for the JTF, but the US and Japanese commanders would be working side-by-side in this case, and they would be working together through all phases of alliance engagement.

Fig. 13.  Possible Arrangement for a Bilateral Task Force/Command in Japan[55]

Several NAC participants thought that this kind of arrangement would be a better way to go in terms of integrating information sharing with logistics support and more time-sensitive missions such as counterstrike and missile defense. One US participant said that an important variable for achieving unified action with a bilateral command is how the allies divide the mission. Another key factor is the amount of compatibility and interoperability that exists between our forces, and to some extent this can be measured by how interchangeable our forces are. Interchangeability can refer to using the same equipment or ammunition, but it can also extend to whole units or platforms, such as either a US or a Japanese destroyer being able to support a particular bilateral mission (and be swapped, one for the other). In this context, “compatible” or “interchangeable” lies somewhere in between allied forces that are simply “deconflicted” on the low end, and fully “integrated” on the high end. If the US and Japan can achieve true interchangeability for certain missions, then unified action is possible under a bilateral command structure.

A US participant reflected on some experience with large-scale bilateral exercises when the two forces experimented with joint activities and creating a bilateral joint operations center for a particular exercise. This involved teaming bilaterally by function and included frequent bilateral briefings for commanders (e.g., update briefing per day, future ops decision brief per day, and a future plans huddle in the evening, etc.). But in after-action reviews the participants generally felt that the arrangement was unrealistic because it would be rare for major bilateral ground units (i.e., a Corps and a Regional Army) to fight so closely together physically. “We need to be able to do that in more distributed way.”

The role of the ACM under the bilateral JTF scenario could be similar to that described for the bilateral staff office, but with one major difference. In addition to addressing SOFA issues and other force management items, the ACM would probably need to be adapted to facilitate high-level political decision making when it comes to the authorized actions of the Bilateral JTF. Military orders will still be determined and carried out in the traditional way, through bilateral consultation and the issuing of coordinated defense orders through the national chains of command, but NAC participants also believed that political oversight and requests for information at the political level related to target selection and force movements would be intense during a crisis. So, when it comes to the actions of a Bilateral JTF requiring well-coordinated and essentially joint decision making at the top levels, a bilateral forum with access to sufficient political authority should be able to interact directly with the Bilateral JTF when necessary. This would not circumvent the legal and traditional chains of command, but the goal would be to tighten the decision-making loop for bilateral action that supplements each country’s own processes for national action.

The ACM has always had a theoretical potential to elevate during a crisis to the NSC-to-NSC level between the two governments, but the process for utilizing this tool has never truly been developed. Had the ACM existed during OPERATION TOMODACHI in 2011, it probably would have been activated at the NSC level to coordinate on difficult decisions regarding fallout from the failing nuclear reactor in Fukushima, but an ad hoc method of bilateral consultation was created instead. The US Embassy in Tokyo was a critical player during that time of crisis, and it will no doubt be an important part of an NSC-led ACM as well, but when military matters are concerned, it will be necessary to have the White House and the Kantei as closely connected as possible. In this situation, the Security Consultative Committee will continue to be an authoritative and deliberative alliance management forum that develops the alliance policy approach to the overall challenge, while the NSC-led ACM (which still includes representation from Foreign and Defense ministries and the military) could make decisions and provide guidance to the military embedded within that policy approach.

Interim Conclusion and Next Steps

The NAC dialogue in Tokyo reaffirmed the importance of recent alliance attention on modernizing C2 arrangements and pursuing closer integration across three main types of alliance interface: 1) political-military, 2) military-to-military, and 3) civilian-military (i.e., a more truly whole-of-government approach). It also underscored the complexity of the issue, the variety of options available, and the need for adjustments by both countries. There is no single obvious solution, but NAC participants were clearly in favor of a more robust bilateral coordination office or command of some kind based in Japan and staffed regularly as a direct link between Japan’s new PJHQ and INDOPACOM from peacetime through to conflict. The good news is that both sides appear to be equally seized with this alliance agenda item, and there appears to be political will in both capitals to work towards a mutually agreed-to scheme for C2 modernization.

NAC participants also generally agreed that necessary alliance adjustments should be determined and implemented as soon as possible, given the dynamic risks the two countries face. For this reason, most endorsed a “building blocks” or “C2 enablers” approach in the short term that does not wait for complete agreement on the C2 end state before taking steps to improve alliance coordination components that we know now will be of value to any future C2 arrangement. In addition, a retired Japanese government official at the NAC recommended that in conjunction with alliance decisions on what the C2 modernization goals and modalities should be, it will be important to prioritize certain steps according to an agreed upon timetable so that the achievement of key milestones can be measured. “We should not just do the easy things first,” he said, “and we should develop an implementation plan according to a timeline and hold ourselves to it.”

For the remainder of 2023 and in the first three months of 2024, our US-Japan Task Force on Command Relationships for New Challenges will reconvene a few additional hybrid roundtables to discuss the three general options in more detail and consider new options. Two areas in particular that the NAC identified in March 2023 but for which there was not sufficient time to discuss, were how US-Japan C2 modernization might relate to US Forces Korea and a North Korean contingency specifically, along with what implications there might be for decision making and deconfliction regarding situations involving nuclear weapons. The Task Force project will also expand the involvement of a diverse group of specialists and stakeholders in the dialogue beyond those already involved. A centerpiece of this workplan will be a second bilateral Track 1.5 NAC in Annapolis, MD in October 2023 (followed by a public event in Washington, DC). We plan to prepare a final Task Force report by the end of March 2024.

Please note that this summary is not a consensus document of the Task Force, and it does not represent the opinions or positions of any of the participating specialists and their organizations. It is a summary prepared by Jim Schoff based on notes from the Spring NAC 2023, prior interviews and roundtables, and from subsequent follow-up discussions with NAC participants. The author is solely responsible for the content of this summary report. Questions or comments regarding this summary can be directed to Jim Schoff at 

About the Author

James L. Schoff became senior director of the “U.S.-Japan NEXT Alliance Initiative” at Sasakawa Peace Foundation USA (based in Washington, DC) in 2021, following nine years as senior fellow and director of the Japan Program at the Carnegie Endowment for International Peace. Prior to that, Schoff served as senior adviser for East Asia policy at the US Office of the Secretary of Defense, contributing to strategic planning and policy development for relations with Japan and the Republic of Korea, as well as spearheading alliance extended deterrence dialogues and trilateral security cooperation initiatives. Schoff’s career spans over thirty years working in the fields of business, education, government, and the non-profit sector, all related to Japan, East Asia, and the US-Japan alliance. Some of his publications include “China and the New Role for Economic Security in the US-Japan Alliance” (Sasakawa Peace Foundation, April 2022), Uncommon Alliance for the Common Good: The United States and Japan after the Cold War (Carnegie, 2017), and “How to Upgrade US-Japan Defense Cooperation” (Carnegie, January 2014).

The US-Japan NEXT Alliance Initiative is a forum for bilateral dialogue, networking, and the development of joint recommendations involving a wide range of policy and technical specialists (in and out of government) to stimulate new alliance connections across foreign, security, and technology policy areas. Established by Sasakawa Peace Foundation USA with support from the Nippon Foundation, the goal is to help improve the alliance and how it serves shared interests, preparing it for emerging challenges within an increasingly complex and dynamic geostrategic environment. Launched in 2021, the Initiative includes two overlapping lines of effort: 1) Foreign & Security Policy, and 2) Technology & Innovation Connections. The Initiative is led by Sr. Director James Schoff.

[1][1] Yuki Tatsumi, “Great Eastern Japan Earthquake: ‘Lessons Learned’ for Japanese Defense Policy,” Stimson Center, November 2021, p. 17. Available at

[2] Ibid, p. 19.

[3] As described by a US Embassy official at the NAC, March 11, 2023.

[4] US Forces Japan website, About USFJ/Our Mission, accessed by the author on April 10, 2023.

[5] Yuki Tatsumi, “Great Eastern Japan Earthquake: ‘Lessons Learned’ for Japanese Defense Policy,” Stimson Center, November 2021, p. 11.

[6] In basic terms, US military joint command arrangements have three levels starting with a Combatant Command at the top, a sub-unified command below (i.e., a subordinate-unified command or joint force command), and finally joint task forces (which are the most specifically tailored). Although a “Joint Force Command” can be used to describe any one of these levels (technically speaking), in this case the participant was referring to the middle level, essentially dual-hatting the Combatant Commander to lead an overall response to a crisis with the support of JTFs and other sub-unified commands.

[7] On establishment of the BJOCC, see Vince Little, “Control Hub Used to Direct Exercise,” Stars and Stripes, November 17, 2007 at

[8] Japan’s Ministry of Defense, Defense of Japan 2022, p. 285.

[9] Ibid.

[10] “Japan and US set up military intelligence team at Yokota Air Base,” Kyodo News, December 18, 2022. Although the BIAC is often referred to as an “intelligence analysis cell” (even in some US press releases), the official English name announced at its launch was “Bilateral Information Analysis Cell.” The Japanese term can mean either.

[11] Comment from USFJ officer at NAC-related event on March 13, 2023.

[12] Japan’s Ministry of Defense, Defense of Japan 2022, p. 286.

[13] James Kraska and Yusuke Saito, “The Law of Military Operations and Self-Defense in the US-Japan Alliance,” Naval War College Review, Summer 2020, Vol 73. No. 3. It is true that the US president must exercise his/her authority within the confines of the US Constitution and can be constrained by Congress over extended periods of time, but the main point is that the US president has far wider discretionary authority to order the use of force compared to Japan’s prime minister.

[14] Ibid.

[15] By “last resort,” Japanese law describes this as a situation “when there is no other appropriate means available to repel the attack and ensure Japan’s survival and protects its people.” See Ministry of Foreign Affairs website, “Japan’s Security Policy: Development of Security Legislation,” at

[16] This is known as the “Law Concerning Measures to Ensure the Peace and Security of Japan in Situations that Will Have an Important Influence on Japan’s Peace and Security.”

[17] Japan’s Ministry of Defense, Defense of Japan 2022, p. 225.

[18] See James L. Schoff, Douglas E. Rake, and Joshua Levy, “A High-Tech Alliance: Challenges and Opportunities for US-Japan Science and Technology Collaboration,” Carnegie Endowment for International Peace, July 29, 2021 at

[19] As presented by a retired Japan Self-Defense Force officer at NAC Tokyo 2023.

[20] See Japan’s Ministry of Defense, Defense of Japan 2009 for reference to JTF-BMD, page 192. For information about North Korea’s launch, see Jon Herskovitz, “North Korea to Launch Rocket,” Reuters, February 19, 2009, at

[21] Japan’s Ministry of Defense, Defense of Japan 2022, p. 214.

[22] Japan’s Ministry of Defense, National Defense Strategy, December 28, 2022 (provisional translation), p. 30, at

[23] A conceptual diagram, as presented by a retired Japan Self-Defense Force officer at a “Bilateral US-Japan Task Force on Command Relationships for New Challenges” roundtable meeting, December 21, 2022.

[24] Kana Inagaki and Leo Lewis, “Is Japan’s Military Fit for Purpose?” Financial Times, May 4, 2023 available at

[25] Yusuke Takeuchi, “Japan’s Self-Defense Forces Miss Recruiting Target by More Than Half,” Nikkei Asia, April 19, 2023.

[26] Regarding the planning committee, see Japan’s Ministry of Defense, Defense of Japan 2022, p. 286.

[27] A conceptual diagram, as presented by a retired Japan Self-Defense Force officer at a “Bilateral US-Japan Task Force on Command Relationships for New Challenges” roundtable meeting, December 21, 2022.

[28] See Section 1087 of the James M. Inhofe National Defense Authorization Act for Fiscal Year 2023, HR 7776, became Public Law No: 117-263 on December 23, 2022. Available on Congress.Gov at

[29] Bryan Clark, “How to Keep Was with China from Being a Pick-up Game,” Defense One, November 2, 2022 at

[30] Admiral Walter F. Doran, “Pacific Fleet Focuses on Warfighting,” August 2003, Proceedings, Vol. 129/8/1,206, US Naval Institute available at

[31] SDF units can use force to defend themselves immediately without Diet approval if they come under attack.

[32] These limitations include the need to conform to a “Basic Response Plan” approved by the Diet, and the use of force must be limited to the minimum extent necessary.

[33] Japan’s Ministry of Defense, Defense of Japan 2022, p. 226.

[34] Ibid.

[35] See “Cabinet Decision on Development of Seamless Security Legislation to Ensure Japan’s Survival and Protect its People July 1, 2014,” available at

[36] See Japan’s Ministry of Defense, Defense of Japan 2022, p. 229.

[37] Japan’s Ministry of Defense, Defense of Japan 2022, p. 278.

[38] See Japan’s Ministry of Defense, Defense of Japan 2019, p. 281.

[39] Adapted by author from a similar chart created by Susumu Nakamura, “The Japanese Response to a Taiwan Crisis—How to Prepare and Respond,” Sasakawa Peace Foundation, June 15, 2021 at

[40] Ministry of Foreign Affairs, “The Guidelines for Japan-US Defense Cooperation,” April 27, 2015, p. 7, at

[41] Tim Starks, “China getting bolder and better in cyberspace, spy chiefs warn,” The Washington Post, March 9, 2023.

[42] See “Joint Cybersecurity Advisory: People’s Republic of China State-Sponsored Cyber Actor Living off the Land to Evade Detection,” issued May 23, 2023 at

[43] Tim Starks, “China will ‘probably’ breach US cybersecurity defenses within 5 years, file says,” The Washington Post, April 25, 2023.

[44] Author interview with a Japanese government official, May 25, 2023.

[45] Author interview with a US military officer, March 13, 2023.

[46] See United Nations Command-Rear on the UNC website at

[47] Gordon Lubold and Ian Talley, “Seven Countries Join to Hunt Ships Smuggling Fuel to North Korea,” The Wall Street Journal, September 14, 2018 at

[48] “Japan Diet Oks Defense Cooperation Pacts with Australia, Britain,” Kyodo News, April 28, 2023 at

[49] Ministry of Foreign Affairs, “The Guidelines for Japan-US Defense Cooperation,” April 27, 2015, p. 4, at

[50] See Japan’s Ministry of Foreign Affairs, “Agreement Between the Government of Japan and the Government of the United States of America Concerning Security Measures for the Protection of Classified Military Information,” August 10, 2007. Available at

[51] A slide presented by a retired Japan Self-Defense Force officer at the March 2023 NEXT Alliance Conference in Tokyo, March 11, 2023. Note: “2015 GL” refers to US-Japan Defense Guidelines agreed to in 2015.

[52] US Department of Defense, “DoD Announces Release of JADC2 Implementation Plan,” March 17, 2022 at

[53] Conceptual org chart prepared by the author, informed by the March 2023 NAC discussion in Tokyo.

[54] Mariel Cooley, “Indo-Pacific Could Serve as Model for Combatant Command Info Sharing,” C4ISNET, December 9, 2022 at

[55] Conceptual org chart prepared by the author, informed by the March 2023 NAC discussion in Tokyo.



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