Shifting the U.S.-Japan Alliance from Coordination to Integration

This week, Tokyo hosted the U.S.-Japan Security Consultative Committee, which brought together the two countries’ defense and foreign ministers. Although these “2+2 meetings” are fairly mundane and routine occurrences, this one had unusual importance: accelerating the shift from coordination to integration. This was the basic task set forth at the April summit between U.S. President Joe Biden and Japanese Prime Minister Kishida Fumio. It represents a significant evolution of the U.S.-Japanese alliance.

For the majority of the alliance’s existence, the United States and Japan had largely separate roles, missions, and capabilities. Japan’s Self-Defense Forces served as the alliance’s defensive “shield,” while the U.S. military provided the offensive “spear.” This shield and spear division of labor gave each ally different tasks, putting the onus on alliance managers to coordinate these distinct lines of effort.

The agreements announced at this spring’s Washington summit and detailed this week in Tokyo signal a turning point toward a more integrated alliance. This includes command and control, defense industrial production and maintenance, and cooperation with other U.S. allies. Alliance integration, in turn, necessitates deeper bureaucratic entanglement on everything from military operations to defense acquisitions to strategic engagement. This is a brave new world that could eventually lead to a fundamental transformation of the U.S.-Japanese alliance.

These integration efforts represent a significant step forward, and, as stated in Tokyo, they are historic. At the same time, they pose the most significant test for the alliance in decades as it seeks to become more robust. In particular, the United States and Japan are likely to confront several challenges that could limit both the speed and scope of their desired vision. If successful, addressing these challenges could fundamentally change the nature of the alliance.

Aligning new American and Japanese command and control arrangements will require the allies to agree on, among other things, the regional scope of U.S. operational commanders in Japan. Deeper defense industry cooperation will likely require the allies to address political and corporate incentives or risk co-production and co-maintenance. Strengthening regional security networks will require discussions with key partners, including Taiwan, which have heretofore been approached with trepidation by Japan. And truly integrating strategies calls for a bureaucratic change in how the United States conceives of allies’ roles in Washington’s strategy development process. While none of these challenges are insurmountable, openly acknowledging them will be vital if the allies are to overcome them.

Upgrading Alliance Command and Control 

A few years ago, Japan stated its intent to create what was then called a permanent joint headquarters to strengthen the effectiveness of joint operations among each of Japan’s Self-Defense Force services. In the subsequent years, that nomenclature changed into what is now called the Japan Self-Defense Forces Joint Operations Command, and many of its details were fleshed out in May 2024. These include establishing it by March 2025 and manning it with roughly 250 people under a four-star flag officer at Japan’s defense ministry in Ichigaya.

Even though that staff size is likely far too small for the Joint Operations Command to be truly effective, its establishment is long overdue. Japan has a chief of staff of its joint staff who oversees the Self-Defense Forces, but he fulfills the military advisory role akin to the U.S. chairman of the joint chiefs of staff, providing strategic-level guidance and advising the prime minister and the defense minister. In peacetime, he is not responsible for day-to-day command decisions, but in wartime, he takes on the added responsibility of operational command of joint operations.

The Joint Operations Command has no U.S. analogue in Japan. At the moment, U.S. Forces Japan is a sub-unified command led by a three-star general without any operational command authority. Instead, it is largely responsible for engaging the Japanese government on all issues that arise under their status of forces agreement. Nevertheless, the Joint Operations Command’s imminent creation has given rise to the need for the United States to revise its command and control framework. The inclusion of command and control adjustments in the April joint statement was therefore widely lauded, carrying the potential to better coordinate bilateral operations.

The challenge, however, lies in what the United States intends to do. Many permutations have been discussed, and many people thought it could take years to conclude the new framework. But in a lightning-short three months, the allies settled on a new command and control structure for the United States. The option endorsed this week will increase U.S. Forces Japan’s operational command authority, allowing it to become something akin to U.S. Forces Korea. It remains to be seen whether this upgraded U.S. Forces Japan will be led by a new four-star commander; for the time being, it will be a three-star. Should a new four-star billet ever be created, that move could invite some level of interservice rivalry and would require Congressional approval. Even the new command idea is likely to encounter some of these challenges. These are real complications, but they could be overcome by deft leadership from the secretary of defense and engagement with members of Congress. They are not insurmountable.

Possibly more difficult are those issues with firmer restrictions. Efforts to make U.S. Forces Japan’s more robust will likely require significant increases in personnel and resources — as well as dedicated forces — all of which could encounter significant resistance due to budgetary realities. Importantly, any U.S. commander responsible for defense of both Japan and the broader region could invite political and legal problems in Japan. The United States will likely want to give this commander an expanded area of operations and flexibility to respond to threats across the theater, which could clash with Japan’s exclusive self-defense policy.

Deepening U.S.-Japan Defense Industry Cooperation

One long-overdue area of cooperation agreed upon in April and reiterated by the ministers this week is more closely integrating the American and Japanese defense industrial bases. Key announcements in this regard covered jointly developing and producing advanced weapons as well as establishing maintenance and repair capabilities in Japan for U.S. ships. In June, the allies held their inaugural Defense Industrial Cooperation, Acquisition, and Sustainment Forum, a newly established group that will identify areas for closer industrial cooperation. The U.S. military-industrial base cannot meet all the requirements for peacetime and wartime, so this approach could help the alliance expand production and sustainment in Japan.

Working together on some mutually beneficial projects should be relatively easy. For example, expanding production of jointly fielded weapons systems that the United States cannot make in sufficient numbers (such as Patriot missiles) makes good sense. Convincing relevant stakeholders, especially defense companies and members of Congress, to adopt this new approach and support production capacity in Japan will still require a substantial political push. One need look no further than the Australia-U.K.-U.S. agreement to see the legal and political challenges facing even the closest U.S. allies on technology sharing and co-production efforts.

Another obstacle is ensuring sufficient manufacturing capacity in Japan. The country’s large defense firms are not accustomed to having defense contracts be a major portion of their business models. Without adapting to the new demands, these firms will remain constrained. This, in turn, could limit the capacity to rapidly expand production for new alliance projects. Moreover, few smaller sub-contractors have the experience or knowledge to work on defense contracts with overseas partners.

An even harder challenge is more administrative in nature. Leveraging Japan’s private sector for dual-use technology and getting civilian researchers to work on defense-related projects have been historically difficult. While this is changing, ongoing information security concerns and a still nascent security clearance system mean the ability to do cooperative alliance work will remain limited for the time being. The 2022 economic security legislation passed by the government and the recent mishandling of classified information show that forward progress is likely to be filled with both positives and negatives. This could inhibit agreement on which advanced technologies or capabilities can be co-developed and co-produced, slowing down progress in these areas.

Bolstering Regional Security Networks

The United States and Japan have made remarkable headway in recent years working with other partners in the Indo-Pacific and beyond. These minilateral arrangements now include the leader-level Trilateral with South Korea, the Trilateral Security Dialogue with Australia, the Quad with India and Australia, and new quadrilateral structures involving the Philippines and Australia. In fact, several of these minilaterals were not only included in the joint statement, they also will be on display this week when the foreign and/or defense ministers from these countries meet in a variety of configurations.

Japan’s involvement in the G7, the Indo-Pacific 4 with NATO, and semiconductor policy cooperation with the United States and the Netherlands is also crucial. Together, these minilaterals demonstrate Japan’s deep integration into the “latticework” the Biden administration has tried to build to connect key democracies on a range of security issues. The next steps will be more difficult, however, since they will require Japan to go beyond traditional areas of cooperation.

Foremost, from an American perspective, is the need to better coordinate with Taiwan on security issues. The military contingency of greatest concern to the United States is one involving China, most likely over Taiwan. Although Japan is pressing ahead with Australia, South Korea, and the Philippines on a variety of initiatives, including security, cooperation with Taipei still lags. There are many reasons for Tokyo’s reticence, including legal constraints and historical precedent. Yet, Japan’s proximity to the Taiwan Strait will require a more forward-leaning approach if maintenance of regional peace and security is Tokyo’s dominant concern. Quiet, substantive, closed-door efforts are more important than loud public signals, but either way, they will require policymakers in Japan to move beyond their comfort zone.

Another area that demands more cooperation is real-time information sharing on air and missile defense. At their recent Trilateral Defense Ministers’ Meeting in Hawaii, leaders from Japan, Australia, and the United States reaffirmed their commitment to missile defense information sharing. Advancing these efforts requires going beyond the old hub-and-spokes model, in which allies share information bilaterally with the United States, and Washington then distributes that data to other allies and partners. Unfortunately, many “trilateral” sharing arrangements have essentially relied on the United States as an information conduit. Direct sharing of information among U.S. allies — without the United States as a middleman — will necessitate cultural changes in Tokyo and other allied capitals, as well as U.S. technical support to establish information sharing networks. As part of this process, Tokyo will have to continue addressing concerns about its information security practices.

Integrating Long-Term Strategies

Perhaps the most difficult challenge the United States and Japan face is truly integrating their long-term strategies, which have heretofore been inter-related but not inter-dependent. Here there is a fundamental asymmetry. Japanese leaders often look to and consult with their counterparts in the United States before devising key strategic documents. On the other hand, while American leaders certainly consider allies when developing strategies, they seldom involve those allies directly in strategy development in the truly formative phases. There are exceptions, such as the U.S. adoption of Japan’s Free and Open Indo-Pacific concept. But American strategists usually develop the core concepts on their own and inform allies afterward. As Washington relies more on allies and partners, especially in a potential Indo-Pacific contingency like a Taiwan invasion, it behooves the United States to more deeply involve allies like Japan early in the conceptual development stages.

Here, the challenges for the United States and Japan are both political and bureaucratic. American strategic documents are usually developed at the beginning of a new administration, which means that they change every four years. If the alterations are marginal, it is possible for allies to adjust their own strategies quickly without a fundamental reimagining. But if the changes are more substantial, allies can get whiplash. This challenge is compounded by bureaucratic obstacles. The authors of the National Security Strategy and National Defense Strategy are often secluded even from their own American colleagues, given the sensitivity of the strategies and a desire to avoid having “too many cooks in the kitchen.” Opening up these processes to key allies is therefore no easy task. It would require a fundamental shift in not just mindset, but also practices that have been in place for decades, allowing allies into the tent at the strategy formulation stage, not just the final polishing phase.

If the United States is interdependent on its allies for its own strategy to succeed, it would benefit Washington to consider finding opportunities to include those allies and partners in their own strategy development processes. To overcome these hurdles, Washington will have to shift from informing its key allies of national strategies to genuinely consulting them early on in the drafting process. U.S. leaders would need to give key allies enough voice to let them suggest changes to elements of the strategies that rely on these allies for success. American officials might not always accept these suggestions, but they must take them seriously in order for allies to feel that they have enough say in the process, particularly if the United States relies on those allies’ compliance to succeed. If U.S. leaders are unable to embrace these adjustments, allies will constantly worry about having the rug ripped out from under them.

Integrated Deterrence in Action?

The joint statement released by the allies this week was truly historic in nature. As important as this agreement is, it is critical to remember that the United States and Japan can no longer simply discuss how to better coordinate with one another. Instead, they should discuss how the American and Japanese systems can work together to address bureaucratic obstacles and political constraints that could hamper deeper integration. The challenges outlined here on command and control, industrial cooperation, regional networking, and long-term strategies are only a handful of the issues that require new approaches. In many ways, these four areas will serve as a test of whether the Biden administration’s “integrated deterrence” strategy is turning from a fashionable buzzword into concrete deliverables. The security situation in the Indo-Pacific demands deeper alliance integration, so the time to deliver is now.

Jeffrey W. Hornung is the Japan lead for the RAND National Security Research Division and a senior political scientist at RAND. He is also an adjunct professor at Georgetown University

Zack Cooper is a senior fellow at the American Enterprise Institute and a lecturer at Princeton University.

Image: Japanese Prime Minister’s Office via Wikimedia Commons