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Operationalizing US Forces Japan

Why Japan Is the Optimal Location for a Joint Force Headquarters

 

Col. Michael Long, US Army

 

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US Forces Japan (USFJ) is undergoing a significant structural upgrade that will increase America’s ability to deter conflict with China and prevail in combat should deterrence fail. Over the next few years, USFJ will transition from an organization focused on alliance management and administration to a joint force command. This shift sets conditions for the development of a more ready and capable response to military aggression from the Chinese Communist Party. Additionally, this updated USFJ is a key step in strengthening the military alliance between Japan and the United States while enhancing interoperability between their militaries.

Deterring China in the Indo-Pacific is a national interest of the United States.¹ The United States has a dual strategy for preventing China from starting a war: deterrence by denial and deterrence by punishment. Deterrence by denial focuses on convincing China that it will fail to achieve a military objective, like conquering and subjugating Taiwan for example. Deterrence by punishment threatens an adversary with a severe repercussion that China would consider worse than the gain of its military objective, such as an overwhelming military response, a nuclear threat, or nonmilitary impositions like economic sanctions. This punishing response could escalate to a world war against China that ends in the death of millions of people and the overthrow of the Chinese Communist Party’s regime.

USFJ is the optimal organization to be a joint force headquarters (JFHQ) because it is central to both deterrence strategies. The command is perfectly positioned in the western Pacific on strategic terrain, and the command and staff have close relationships with key military leaders in allied nations like Japan and the Republic of Korea. USFJ is comprised of component commands arrayed across Japan including the 5th Air Force; Commander, Naval Forces Japan; US Marine Corps Forces Japan; US Army Japan; and US Space Forces Japan.² Its location and forces offer a myriad of opportunities to exercise a joint force command. Transformation of USFJ into a JFHQ that can command US and allied forces across all domains from crises to combat is an essential addition to America’s deterrence strategy. However, there still is not an officially approved program of record for the future of military command-and-control acquisitions.

Background

Although American forces have been stationed in Japan since 1945, USFJ was not formally established until 1957, replacing the Far East Command.³ Until recently, the role of USFJ has been primarily administrative, focusing on maintaining the US-Japan bilateral alliance and serving as the higher headquarters for its subordinate commands postured across the island nation. However, this antiquated role began to change in 2024.

During the US-Japan Security Consultative Committee Meeting in July 2024, Secretary of Defense Lloyd Austin, Secretary of State Antony Blinken, and their Japanese counterparts agreed to enhance their respective capabilities for deterrence and crisis response to uphold the free and open rules-based international order.⁴ The Department of Defense (now War) announced it would “expand its missions and operational responsibilities … the most significant change to USFJ since its creation—and one of the strongest improvements to the Alliance’s military cooperation in seventy years.”⁵ Congress validated this requirement in the 2025 National Defense Authorization Act, directing the department to “plan for the establishment of joint force headquarters subordinate to U.S. INDOPACOM in Japan.”⁶

In February 2025, President Donald Trump met then–Japanese Prime Minister Shigeru Ishiba and agreed to continue the improvement of USFJ.⁷ The following month, during Secretary of War Pete Hegseth’s first trip abroad, he visited Tokyo to announce Phase One of the command’s upgrade to a JFHQ.⁸ This phase focused on improving command and control, responsiveness, and interoperability.

This transformation is driven by increased PRC aggression and the corresponding deteriorating relations between China and Japan. In the last two decades, China has vastly increased its military capabilities, sanctioned Japanese trade, conducted a series of gray-zone activities, stolen natural resources, and disputed Japan’s territorial sovereignty.⁹

These increasingly hostile actions have strengthened the US-Japanese alliance. In 2022, in his National Security Strategy, Ishiba deemed China as the country’s greatest threat.¹⁰ For the first time in over forty years, China’s threat to Japan surpassed that of North Korea. As Japan refocuses its national strategy, it is bolstering its military capabilities to deter future conflict and growing in parallel with the USFJ.

US Forces Japan as a Joint Force Command

The USFJ transform is intended to shift the organization into an operational headquarters that can effectively command and control multidomain forces across the competition continuum from disaster relief efforts to large-scale combat operations. Several changes to USFJ’s staff, infrastructure, and subordinate commands will be necessary to accomplish this transition.

Joint Publication 3-33, Joint Force Headquarters, describes the staff’s role in a JFHQ as providing supervision of the seven joint functions: command and control, intelligence, fires, movement and maneuver, information, sustainment, and protection.¹¹ This expertise must be added to the staff. Additionally, USFJ will need to add redundant capabilities so it can sustain twenty-four-hour operations across all the joint functions. Bolstering the staff will require increasing personnel levels—service members and civilians with critical capabilities—well beyond what the organization has historically required to run a more administrative headquarters. USFJ is currently using augmentees to fill most of these additional requirements but will need a significant permanent contribution from across the joint force in the future.

Structurally, USFJ will need a world-class suite of infrastructure to command and control operations across a vast area of operations. Gen. Ron Clark, US Army Pacific commander, describes the Indo-Pacific as ranging from “Bollywood to Hollywood and polar bears to penguins.”¹² This area is vast with more sea, land, cyber, and people than any other combatant command.¹³ The infrastructure to command and control multiple joint operations throughout the Indo-Pacific requires a joint operations center that can accommodate this growing staff, as well as upgraded software. However, all these upgrades will need to be interoperable with the Japanese Self-Defense Forces (SDF) and each service of the joint force and the interagency. Companies like Anduril, Lockheed Martin, and Palantir are working on these software solutions, but there still is not a codified system of record for the future.¹⁴

A JFHQ is comprised of not just the command and staff, but also its component commands. USFJ has operational control of commands from the Army, Air Force, Navy, Marines, and Space Force. These component commands will have increased responsibilities and authorities as both service component commands and functional component commands. For example, US Army Japan (USARJ) will serve as both the service component command, Army forces command (ARFOR), and the functional component command, land component command (LCC). These dual roles require additional staff, assets, and infrastructure for USARJ to be capable of effectively accomplishing both roles for the JFHQ. In this Army example, USARJ, as the ARFOR, will likely need additional assets to accomplish additional missions with its new role, especially Army support to other services during sustained operations. These requirements, as explained in Field Manual 3-94, Armies, Corps, and Division Operations, include transportation, fuel distribution, logistics management, medical evacuation, communication, and many others.¹⁵ USARJ is currently a relatively small headquarters with minimal enablers. To become the LCC and ARFOR for a JFHQ in crisis response operations, this small administrative command requires considerable growth in staff, infrastructure, and subordinate commands.

Exercising the Joint Force Headquarters

To build readiness, USFJ will not only need to add these capabilities, but the organization will also need to exercise them regularly across all domains. Other than its key geographic location, the most significant advantage of this command is the vast number of training opportunities. The US military conducts dozens of joint, interagency, and combined exercises across the Pacific every year. The US Army alone is part of three land exercises (Yama Sakura, North Wind, and Orient Shield) and four joint exercises (Keen Edge, Keen Sword, Resolute Dragon, and Freedom Edge) with the Japanese SDF.¹⁶

Trilateral exercises. Trilateral exercises are an even better training opportunity for the JFHQ. For example, the US Navy, the Republic of Korea Navy, and the Japan Maritime SDF have conducted multiple trilateral exercises in the Pacific. Utilizing USFJ as the command-and-control headquarters for multiday exercises involving military assets from three countries across all domains is the type of world-class training needed to be prepared to fight a near-peer military like the People’s Liberation Army (PLA).

Freedom of navigation operations. Freedom of navigation operations are another key training opportunity for a JFHQ. The United States and Japan regularly conduct freedom of navigation operations in the disputed waters of the South China Sea and the Sea of Japan/East Sea.¹⁷ These are serious operations bordering Chinese waters that are often contested by military displays of the People’s Liberation Army Navy (PLAN) and PLA Air Force.¹⁸ These operations require an entire JFHQ staff and component commands to act in concert to command and control forces, assess and predict adversary actions, conduct information operations, and plan for potential targeting requirements.

Humanitarian assistance and disaster response operations. USFJ, as a JFHQ, will be perfectly suited for humanitarian assistance and disaster response operations. The US military often provides the first international response to the world’s worst natural disasters, and when these disasters occur in the Pacific, USFJ is an ideal organization to command and control US and international response operations. The quick convergence of civilian and military assets and organizations on a chaotic environment in a no-fail mission simulates much of the environment and missions of combat. As a JFHQ, USFJ can improve the speed and quality of humanitarian assistance and disaster response operations while improving readiness.

Japan’s Role in USFJ’s Transition

The government of Japan is not only allowing the United States to upgrade its military capability in Japan, but it is also building alongside the new command. In March 2025, as part of the Defense Buildup Program, it established the Japan SDF Joint Operations Command (JJOC), which is to build a system capable of seamlessly conducting cross-domain operations at all stages from peacetime to contingency, with the aim of strengthening the effectiveness of joint operations among each SDF services.¹⁹ This new command is led by a lieutenant general, the same rank as the Japan SDF’s chiefs of staff.

Part of transforming USFJ into a JFHQ is leveraging the JJOC. Lt. Gen. Stephen Jost, the USFJ commander, developed a JJOC Cooperation Team (JCT) as a standing organization collocated in Tokyo. The JCT is the primary liaison between the upgraded USFJ and the JJOC to avoid the “ad-hoc” nature common with joint operation headquarters during crisis response operations.²⁰

While still a relatively small organization, the JJOC will likely need to grow its 250-person command to be prepared for large-scale crisis response operations. However, the authority of the commander and the commensurate rank are a starting point. The physical proximity of the JCT in Tokyo near Japan’s Ministry of Defense, permanently manned with military expertise, is a key first step in developing the interoperability required to successfully conduct combined joint operations across multiple domains with key Pacific allies. Although JJOC and JCT will require additional upgrades to be optimized for their respective missions, they are foundational to developing the capability to conduct crisis response operations from natural disasters to large-scale combat.

Conclusion

Deterring conflict with China in the Indo-Pacific is a critical US military objective that requires well-trained operational commands capable of running joint operations across all phases of the competition continuum. USFJ is positioned on strategic high ground west of the International Date Line, relatively near Taiwan. It is comprised of a joint force of sixty-five thousand troops and civilians dedicated to deterrence. USFJ is the operational link between the US military and allies in the region. The transition of USFJ from administrative to operational as a joint force command is a necessary step to deter conflict with China in the Indo-Pacific. If deterrence should fail, this frontline unit will be in operational control of much of the fight. However, conducting the transformation is only the first step. While conducting this research, five questions surfaced that warrant further exploration to most effectively build this valuable capability.

1. Should the Department of War combine the commands of USFJ and US Forces Korea into a single four-star, sub-unified JFHQ?
2. Is there a potential to combine USFJ and the JJOC in a bilateral combined forces command like the model used in the Republic of Korea?
3. What enabling commands will USARJ need to successfully conduct its roles as LCC and ARFOR for the joint force command in sustained large-scale combat operations?
4. What joint commands should be the bill payers for the joint personnel needed in USFJ, and what Army commands should be the bill payers for USARJ staff positions and potential additional commands?
5. When USARJ combines with 4th Multi-Domain Task Force and converts to Multi-Domain Command-Japan, how will the effect its ability to act as component command for USARJ?²¹ Is this a role Eighth Army in Korea could take on?

While there is still considerable work to be done across the Department of War, it is clear the US Indo-Pacific Command is gaining a key enabler for the strategy of deterrence. USFJ can be the model on how the United States could respond to potential Pacific conflicts of the future.

The views expressed are my own and not necessarily those of the Department of War, the US Army, or the Army War College.

 

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Notes

1. Office of the Secretary of War, Fiscal Year (FY) 2026 President’s Budget: Justification for Security Cooperation Program and Activity Funding (US Department of War [DoW], June 2025), https://comptroller.war.gov/Portals/45/Documents/defbudget/FY2026/FY2026_Security_Cooperation_Justification_Book.pdf.
2. “Unit Links,” US Forces Japan, accessed 6 April 2026, https://www.usfj.mil/.
3. “About USFJ,” US Forces Japan, accessed 6 April 2026, https://www.usfj.mil/About-USFJ/.
4. “Fact Sheet: Joint Statement of the Security Consultive Committee (‘2+2’),” US DoW, 28 July 2024, https://www.war.gov/News/Releases/Release/Article/3852200/fact-sheet-joint-statement-of-the-security-consultative-committee-22/.
5. “Fact Sheet: Joint Statement.”
6. US National Defense Authorization Act for 2025, Pub. L. No. 118-159, 138 Stat. 1773, https://www.congress.gov/118/plaws/publ159/PLAW-118publ159.pdf.
7. “United States–Japan Joint Leaders’ Statement,” White House, 7 February 2025, https://www.whitehouse.gov/briefings-statements/2025/02/united-states-japan-joint-leaders-statement/.
8. US DoW, “Secretary of Defense Pete Hegseth Concludes Visit to Japan,” news release, 30 March 2025, https://www.war.gov/News/Releases/Release/Article/4139267/secretary-of-defense-pete-hegseth-concludes-visit-to-japan/.
9. Dragos Ionita, “From Partners to Rivals: Why China-Japan Relations Are Spiraling,” Geostrategic Media, 30 November 2025, https://geostrategicmedia.com/2025/11/30/from-partners-to-rivals-why-china-japan-relations-are-spiraling/.
10. Japan Ministry of Defense, National Security Strategy of Japan (Japan Ministry of Defense, December 2022), https://www.cas.go.jp/jp/siryou/221216anzenhoshou/nss-e.pdf.
11. Joint Publication 3-33, Joint Force Headquarters (US Government Publishing Office, July 2024, change 1).
12. Liu Xuanzun et al., “US Army’s Dispersed New Units Targeting China in Conflict to Face Logistics, Comms, Air Defense Problems: Expert,” Global Times, 5 March 2025, https://www.globaltimes.cn/page/202505/1333357.shtml.
13. “About USINDOPACOM,” Headquarters, United States Indo-Pacific Command, accessed 6 April 2026, https://www.pacom.mil/about-usindopacom/.
14. Marcus Rodriguez, “AI in Defence Market Share: Palantir, Lockheed, Anduril Solidify 2025 Leads,” Business 2.0, 19 November 2025, https://business20channel.tv/ai-in-defence-market-share-palantir-lockheed-anduril-solidify-2025-leads.
15. Field Manual 3-94, Armies, Corps, and Division Operations (US GPO, July 2021).
16. “Exercise Yama Sakura,” Defense Visual Information Distribution Service (DVIDS), accessed 6 April 2026, https://www.dvidshub.net/feature/YamaSakura73; “North Wind 25,” DVIDS, accessed 6 April 2026, https://www.dvidshub.net/feature/NW25; “Orient Shield 25,” DVIDS, accessed 6 April 2026, https://www.dvidshub.net/feature/OrientShield25; “Keen Edge,” DVIDS, accessed 6 April 2026, https://www.dvidshub.net/feature/keenedge; “Keen Sword,” DVIDS, accessed 6 April 2026, https://www.dvidshub.net/feature/KeenSword; “Resolute Dragon 2025,” DVIDS, accessed 6 April 2026, https://www.dvidshub.net/feature/ResoluteDragon25; U.S. Indo-Pacific Command Public Affairs, “Freedom Edge 2025: Building Trilateral Trust Across the Indo-Pacific,” US Navy, 19 September 2025, https://www.navy.mil/Press-Office/News-Stories/display-news/Article/4308744/freedom-edge-2025-building-trilateral-trust-across-the-indo-pacific/.
17. Eleanor Freund, Freedom of Navigation in the South China Sea: A Practical Guide (Belfer Center for Science and International Affairs, Harvard Kennedy School, June 2017), https://www.belfercenter.org/sites/default/files/pantheon_files/files/publication/SCS%20Report%20-%20web.pdf; Tetsuo Kotani, Freedom of Navigation and the US-Japan Alliance: Addressing the Threat of Legal Warfare (Japan Center for International Exchange, December 2011), https://jcie.org/wp-content/uploads/2021/07/USJapanPapers-Kotani.pdf.
18. Hu Yuwei et al., “Chinese Report Challenges Legality of US ‘Freedom of Navigation’ Operations,” Global Times, 25 August 2025, https://www.globaltimes.cn/page/202508/1341650.shtml.
19. Dzirhan Mahadzir, “Japan Stands Up New Joint Operations Command Planned to Work with Local U.S. Forces,” US Naval Institute, 25 March 2025, https://news.usni.org/2025/03/25/japan-stands-up-new-joint-operations-command-planned-to-work-with-local-u-s-forces.
20. Gabriel Dominguez, “Coordination Office Marks First Step in U.S. Forces Japan’s Shift to ‘Warfighting’ Command,” Japan Times, 31 July 2025, https://www.japantimes.co.jp/news/2025/07/31/japan/us-military-japan-upgrade/.
21. Andrew Feikert, “The Army’s Multi-Domain Task Force (MDTF)” (Congressional Research Service, 30 June 2025), https://www.congress.gov/crs_external_products/IF/PDF/IF11797/IF11797.22.pdf.

 

 

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