Deepening Strategic Alignment: Priorities for the U.S.-Japan Alliance

The Trump administration has welcomed Japan’s plans, which dovetail neatly with the emphasis on increased burden sharing by allies in the U.S. National Security Strategy released in 2025.⁴ Economic security also featured prominently in the document, defined broadly to include issues such as trade and energy dominance in addition to securing critical supply chains. The 2026 U.S. National Defense Strategy somewhat reflects Japan’s strategic priorities in referencing deterrence vis-à-vis China, defense of the First Island Chain, and a more robust defense industrial base, but diverges markedly from previous U.S. administrations by identifying the Western Hemisphere as a strategic priority, downplaying the North Korea and Russia threats, and framing its treatment of allies strictly in the context of burden sharing rather than as a foundational element of U.S. strategy.⁵ The evolving conflict following strikes by the United States and Israel on Iran on February 28, 2026, has also raised questions about the overall trajectory of U.S. security policy.

The imperfect alignment of their respective strategic blueprints notwithstanding, President Trump and Prime Minister Takaichi, during bilateral summit meetings in October 2025 and March 2026, reaffirmed a shared commitment to strengthen diplomatic, defense, trade, and economic security cooperation under Japan’s Free and Open Indo-Pacific (FOIP) construct.⁶ Although bilateral cooperation continues to proceed relatively smoothly at the operational level, there is a pressing need to articulate a strategic vision to guide alliance priorities and facilitate effective implementation of common objectives.
 

U.S.-Japan Alliance Cooperation: Progress, Challenges, Opportunities

This section assesses the current state of U.S.-Japan alliance cooperation and highlights challenges and opportunities in several key areas: alliance coordination, deterrence and response capabilities, defense industrial base cooperation, cybersecurity and intelligence sharing, and burden sharing. 

Alliance Coordination

Strengthening command and control capabilities and joint operational readiness has been a major focus of U.S.-Japan alliance efforts. In 2024, plans were announced to transform U.S. Forces Japan into a joint operational headquarters serving as a counterpart to Japan’s Joint Operations Command (JJOC) to enable faster, more synchronized decisionmaking and more effective operational planning for a full range of contingencies, from gray zone scenarios to military conflicts to disaster relief.⁷ Despite some initial reports that the Pentagon was considering canceling the restructuring of U.S. forces in Japan, the Trump administration confirmed that it would proceed with existing plans.⁸ Japan has taken the lead by establishing the JJOC in March 2025 to organize and command Self-Defense Forces responses to all crises, contingencies, and natural disasters. In August 2025, the first wave of rotational personnel arrived in support of the U.S. transformation to a Joint Force Headquarters, and in January 2026 the two governments reaffirmed efforts to continue upgrading alliance command and control structures.⁹

However, it is critical to sustain momentum for implementation of these plans, given that challenges remain in terms of both domestic institutional changes by each country and bilateral coordination. At the broadest level, there is a need for robust dialogue about the division of roles, missions, and capabilities in the U.S.-Japan alliance and how this will translate into an effective bilateral decisionmaking architecture. Initial plans are important steps in the correct direction, but greater clarity is needed regarding how the new command and control structure will operate in practice. For example, moving operational command authority closer to the front line of the theater is intended to mitigate potential delays associated with having a command in Hawaii, but questions remain about the extent to which the new U.S. Joint Force Headquarters will be empowered vis-à-vis U.S. Indo-Pacific Command and how exactly the decisionmaking and response process will work in practice.

The ability of the United States and Japan to expedite response times and facilitate more effective operations across military domains will depend on how well they can integrate their respective decisionmaking architectures, so it is necessary to have both a roadmap and continual consultation about the implementation process. An initial step could be to identify the key missions that will benefit the most from leveraging the integrated assets of both countries and to build the coordination architecture from there. Discussions such as these have traditionally been spearheaded through forums such as the Security Consultative Committee (2+2), which has not met since 2024.¹⁰ Integrating command and control functions sends an important signal about interoperability, which is foundational to strengthening alliance deterrence and response capabilities. 

Deterrence and Response Capabilities

Japan has taken important actions to enhance its defense capabilities in recent years, including boosting its overall level of defense spending to 2 percent of its gross domestic product (see Figure 1) and acquiring a number of new assets, including long-range counterstrike weapons, that augment its deterrence and response capabilities. Notable legal and political constraints remain on the use of such capabilities by Japan, but they serve to bolster U.S. extended deterrence. Under the Trump administration, the United States has repeatedly reaffirmed its commitment to the defense of Japan, using the full range of U.S. defense capabilities, including nuclear.¹¹ However, the U.S. government has simultaneously made it clear that it expects allies and partners to do more for their own defense, and its growing military engagement in the Middle East has raised questions about the U.S. capacity to maintain effective extended deterrence in Asia.

Although investments in defense are positive and necessary developments, there is a risk that the arrival of new capabilities may precede the construction of mechanisms necessary to use these capabilities effectively in the context of the U.S.-Japan alliance. For example, in the case of Japan’s new counterstrike capabilities, further discussion is necessary to clarify how they will be integrated with the United States in terms of information sharing, targeting, real-time decisionmaking, and operational division of labor. Similarly, discussions in Japan regarding potential acquisition of next-generation submarines and other exquisite systems sometimes seem to precede serious discussion of the cost and strategic value of these assets.¹² Instead, the goals should lead, and the capabilities should follow. For example, the war in Ukraine has clearly demonstrated the vulnerability of sophisticated systems and the strategic value of low-cost, high-volume assets.

Similarly, strengthening extended deterrence requires a serious consideration of what the nuclear landscape will look like in 10 years and beyond if the nuclear arsenals of China and North Korea continue to grow. In addition to ongoing efforts such as the U.S.-Japan Extended Deterrence Dialogue, new initiatives may be necessary to reassure Japan and other allies about U.S. commitments. In contrast to South Korea, where there has been an active public debate about acquiring nuclear weapons, discussion of this topic in Japan has been relatively muted. NATO-style nuclear sharing was briefly debated and generally dismissed in Japan in 2022, but an anonymous quote from a Japanese government official in December 2025 suggesting that Japan should discuss the nuclear option stimulated a debate about potentially revising its three nonnuclear principles.¹³

Expectations for Japan’s leadership role will likely continue to increase in the face of multiple security challenges, further amplifying the importance of bilateral coordination on Japan’s plans for acquiring advanced defense capabilities and how these capabilities could be used in specific contingencies. For example, the conflict in Iran has prompted debate about Japan’s legal constraints with respect to the use of military force and the conditions under which Japan could dispatch its Self-Defense Forces to support U.S. operations by exercising collective self-defense based on a series of defense policy reforms instituted in 2015.

Defense Industrial Base Cooperation

The Trump administration has identified bolstering the U.S. defense industrial base as a core priority in both the National Security Strategy and the National Defense Strategy, and it has called upon allies and partners to enhance their own defense industrial bases to strengthen collective self-defense. This is another area where Japan’s strategic direction demonstrates complementarity with U.S. objectives. Japan has been strengthening its own defense industrial base over the past decade, resulting in its most consequential defense sale to date in August 2025 when Japan’s Mitsubishi Heavy Industries was selected for a $6.5 billion deal to build warships for the Royal Australian Navy. Under Prime Minister Takaichi, the Japanese government plans to scrap existing restrictions limiting Japan’s defense exports to five nonlethal categories (rescue, transport, reconnaissance, surveillance, and minesweeping) and instead classify defense equipment into two categories (lethal and nonlethal).¹⁴ Although there will likely be limitations on the transfer of lethal equipment, the change will enable Japan to deepen security partnerships with the United States and other like-minded countries.

These trends point to ways that both the United States and Japan can strengthen their respective defense industrial bases while also bolstering their mutual security. For example, at the March 2026 summit in Washington, Prime Minister Takaichi and President Trump agreed to further strengthen alliance deterrence and response capabilities, namely the codevelopment and coproduction of missiles, including scoping Japan’s future role in supporting Advanced Medium-Range Air-to-Air Missile (AMRAAM) production capacity and the accelerated production of Standard Missile 3 Block IIA missiles in Japan to bolster missile defense cooperation.¹⁵

However, aside from pursuing new areas of coproduction and codevelopment, there is work to be done to lower barriers to purchasing U.S. defense equipment by reforming the Foreign Military Sales process and improving delivery times, challenges the Trump administration has already identified in an executive order and in dialogues with Japanese counterparts.¹⁶ It is also important to note that the current U.S. emphasis on allies doing more for their own defense is consistent with a potential revival of indigenous defense production in Japan.¹⁷ The Japanese government may be pushed further in this direction as the security environment continues to deteriorate if it encounters persistent challenges in working with the United States on acquisition and development. While indigenous production may have some benefits, it can also result in higher costs and less effective capabilities. Therefore, common strategic objectives under the U.S.-Japan alliance must be continuously reaffirmed to ensure the most efficient mix of defense purchases, codevelopment, coproduction, and indigenous production.

Cybersecurity and Intelligence Sharing

Enhancing cybersecurity and facilitating intelligence sharing are crucial to strengthening U.S.-Japan alliance cooperation, and the Japanese government has recently stepped up its efforts in these areas. In May 2025, Japan implemented a new national security clearance system and enacted new active cyber defense (ACD) legislation that enables the government to collect and share foreign data related to suspected cyberattacks passing through Japan, mandates reporting of cybersecurity incidents by operators of critical infrastructure, and streamlines related institutions. This legislation is intended to facilitate more rapid threat response, intelligence sharing, and international cooperation. At the March 2026 U.S.-Japan summit, Tokyo committed to developing a secure and sovereign cloud platform for government data to enhance information sharing, planning, and coordination. In addition, the Takaichi administration has put forward a proposal to strengthen and centralize Japan’s intelligence community by creating a National Intelligence Agency (to replace the Cabinet Intelligence and Research Office), a National Intelligence Council (to replace the Cabinet Information Council), a Foreign Intelligence Agency, and a cross-intelligence community training institution. The Japanese government also plans to begin deliberations to draft and enact new intelligence and anti-espionage legislation.¹⁸

These are important steps toward enhancing Japan’s information security and enabling better intelligence sharing with the United States, but implementation of these policies is still at an early stage and significant challenges remain. Concerns about the Japanese government’s ability to protect sensitive information persist, despite recent improvements. The division of labor and integration among the new institutions created by the ACD legislation and the proposed intelligence reforms remain unclear, as do the mechanisms for these new institutions to interact with their counterparts in the United States. Due to privacy considerations, gaps in government monitoring exist in terms of the ability to monitor domestic communications in which both the sender and recipient are located in Japan. Public-private sector cooperation on cybersecurity is improving but needs to be strengthened still further to better facilitate reporting and response. When it comes to implementing ACD, effective intelligence sharing infrastructure and processes are essential, and attribution and determining thresholds for action will require close consultation with the United States. In addition, cultivating a skilled workforce equipped to work with cybersecurity and intelligence issues will require long-term investment in training and recruitment.

Burden Sharing

The Trump administration has clearly called upon U.S. military allies, including Japan, to do more for collective defense, including increasing their own defense spending and investing in capabilities aimed at deterring aggression. The 2026 U.S. National Defense Strategy advocates for a new global standard of 5 percent of GDP for defense spending among all U.S. allies and partners: 3.5 percent on core military spending and 1.5 percent on security-related spending. As discussed previously, Japan has already taken significant steps to accelerate its planned defense spending increase to 2 percent of GDP. Many experts have referred to this as being acknowledged as the new “floor” for defense spending, and defense spending has already been identified as a priority area by Prime Minister Takaichi.¹⁹ Overall, Japan’s increased investments in advanced defense capabilities reflect a desire to realize a more equal division of labor under the U.S.-Japan alliance. This marks a dramatic departure from Cold War–era policies centered on Japan doing the minimum necessary for defense while relying on U.S. commitments under the bilateral security treaty.

However, there are two important caveats to this emphasis on defense spending. First, the quality of defense spending is just as important as the quantity of defense spending. Simply focusing on spending targets may distract from the primary goal of aligning spending priorities with common strategic objectives to strengthen the U.S.-Japan alliance and substantively improve deterrence and response capabilities. As the Takaichi administration prepares a new defense procurement plan to be unveiled by the end of 2026, there is an urgent need for Tokyo and Washington to think carefully about how to allocate resources and ensure alliance interoperability in an increasingly complex security environment.

Second, burden sharing should be conceptualized to include contributions by allies beyond the area of traditional military security. The 2025 U.S. National Security Strategy emphasizes that economic security is fundamental to national security, and it identifies balanced trade, access to critical supply chains and materials, reindustrialization, reviving the defense industrial base, energy dominance, and financial sector dominance as key aims. Consequently, the United States has asked Japan and other allies to do more not only in terms of defense spending, but also in trade, investment, and economic security; these contributions should therefore be considered comprehensively when evaluating burden sharing. Again, this is an area where the interests of the United States and Japan are generally well aligned, though there are differences in the two governments’ approaches to economic security policy. Japan was the first country to enact comprehensive economic security legislation in 2022, and it has been an early mover in recognizing the threats posed by supply chain disruptions and economic coercion to national security.

The Japanese government has taken seriously the strong emphasis of the Trump administration on the interconnections between economic security and military security, so its actions should be viewed comprehensively as contributions to U.S. national interests—particularly because they all involve significant commitments of financial resources. For example, in June 2025, the government of Japan committed to investing $550 billion in the United States to advance economic and national security interests, including but not limited to semiconductors, pharmaceuticals, metals, critical minerals, shipbuilding, energy, artificial intelligence, and quantum computing, and the first six investment projects were announced in February and March of 2026. Table 1 illustrates some of the commitments made by Japan in military security, economic security, and trade and investment since the beginning of the second Trump administration.

Partnerships and Coalition Building

Given the complex challenges facing the United States and Japan, successive political administrations in both countries have increasingly recognized the importance of building regional and global partnerships. Japan has developed and adapted its Free and Open Indo-Pacific (FOIP) vision as a framework for its regional engagement, and many similar elements were reflected in the Indo-Pacific Strategies of the first Trump and Biden administrations. Small minilateral groupings have become notably more prominent parts of the Indo-Pacific regional institutional architecture. For example, the Quad, which brings together the United States, Japan, Australia, and India, was revived under the first Trump administration and elevated to the leader level during the Biden administration.²⁰ A host of other regional trilateral groupings have solidified in recent years, as well as cross-regional groupings such as the NATO Indo-Pacific 4, which brings together U.S. allies in Europe with Australia, Japan, New Zealand, and the Republic of Korea. Both the United States and Japan have been central to this emergent minilateral architecture.

Although the beginning of the second Trump administration marked an explicit return to an “America first” foreign policy, the United States has continued to recognize the strategic value of some of these minilateral groupings to its national interests, particularly in the Indo-Pacific region.²¹ Engagement with groupings such as the U.S.-Japan-Republic of Korea trilateral, the Quad, and the “Squad” (U.S.-Australia-Japan-Philippines) has continued, for example.²² The United States has also created new minilateral initiatives such as Pax Silica and reshaped groupings like the Minerals Security Partnership, which is now the Forum on Resource Geostrategic Engagement (FORGE). Japan is involved in many of these new efforts. To some extent, fluctuation in this ad hoc minilateral institutional architecture is predictable, considering the shifting international environment and the desire of new U.S. administrations to create novel initiatives.

However, there are some areas of concern when it comes to U.S.-Japan alignment on broader Indo-Pacific partnerships. First, it is not clear whether the second Trump administration can or will prioritize the Indo-Pacific to the same extent as previous U.S. administrations, despite references to Japan’s FOIP.²³ The U.S. National Security Strategy and National Defense Strategy display inconsistent attention to Indo-Pacific threats and opportunities, and U.S. military interventions in Venezuela and Iran point to a shift in Washington’s focus to other parts of the world. The United States has already moved military assets from the Indo-Pacific to the Middle East in response to the Iran conflict.²⁴ Second, U.S. economic policy has created tensions in the Indo-Pacific that have made it difficult to pursue regional diplomatic partnerships. For example, U.S.-India tensions have effectively stalled leader-level Quad meetings, and many Indo-Pacific countries have felt the negative impacts of U.S. tariffs and the halt to U.S. foreign aid. There is no longer a positive economic component to Washington’s Indo-Pacific engagement, which makes it more difficult to build regional coalitions around shared interests. Third, the Trump administration’s disinterest in the normative dimensions of regional strategy complicates bilateral agenda setting under FOIP, which centers fundamentally on preserving a rules-based order regionally and globally.²⁵

At this moment, Japan has an important opportunity to take a leadership role in sustaining and building regional partnerships, both in direct cooperation with the United States and in parallel with like-minded U.S. allies and partners. With respect to U.S. involvement, critical minerals, energy, and emerging technologies present potential opportunities for driving collaboration. The growing challenges posed by cooperation among China, Russia, Iran, and North Korea also provide a strong impetus for Tokyo and Washington to coordinate avenues for enhanced security cooperation with other relevant partners. In parallel, Japan is likely to find opportunities to foster dialogue among like-minded countries in the Indo-Pacific, Europe, and elsewhere on trade, foreign aid, maritime governance, climate change, and other issues that are not currently the focus of the Trump administration but still require strong regional and international leadership. For example, expansion of the Comprehensive and Progressive Trans-Pacific Partnership could further cement Japan’s leadership in regional trade liberalization and economic integration. Japan has also steadily strengthened its security partnerships with countries such as Australia, the Philippines, and the United Kingdom, which complements its alliance with the United States.
 

Policy Recommendations

As Japan prepares to revise its three strategic documents, it is a particularly important time for Tokyo and Washington to reaffirm their strategic alignment and to put forward a roadmap for deepening cooperation in the future. This brief highlights several opportunities to strengthen bilateral cooperation to usher in a new phase of U.S.-Japan alliance cooperation under the Takaichi and Trump administrations. Key recommendations include the following:

• In addition to continuing strong cooperation at the operational level, the United States and Japan should rebuild momentum for high-level strategic discussions, including resuming Security Consultative Committee (2+2) talks among their foreign and defense ministers.
• The United States and Japan should reinvigorate bilateral dialogue on roles, missions, and capabilities in the alliance and how command and control integration will translate into an effective bilateral decisionmaking architecture.
• As both countries take steps toward strengthening their respective defense industrial bases and furthering defense industrial cooperation, the United States and Japan should consider the most efficient mix of defense purchases, codevelopment, coproduction, and indigenous production.
• As Japan increases its defense capabilities, it should engage in bilateral discussions to clarify how these new capabilities will be integrated with the United States in terms of operational division of labor, information sharing, targeting, and real-time decisionmaking.
• In addition to ongoing efforts such as the U.S.-Japan Extended Deterrence Dialogue, the United States and Japan should consider new initiatives to strengthen extended deterrence in light of the growing nuclear arsenals of China and North Korea.
• The United States and Japan should step up contingency planning for shared threats in the Indo-Pacific region, as well as consider how they might coordinate in extra-regional crises such as the current Middle East conflict.
• The United States should continue efforts to lower barriers to purchasing U.S. defense equipment by reforming the Foreign Military Sales process and improving delivery times to facilitate cooperation with Japan and other allies.
• Japan should continue to strengthen its laws and institutions for cybersecurity and intelligence sharing in close consultation with the United States. The two governments should sustain senior level dialogue on cybersecurity to assess the implications of Japan’s new active cyber defense policy for bilateral cooperation.
• The United States should consider defense, economic security, trade, and investment when evaluating Japan’s contributions to alliance burden sharing and de-emphasize transactional diplomacy in favor of comprehensive bilateral agenda setting.
• The United States and Japan should further deepen areas of alignment for regional partnerships in the Indo-Pacific in areas such as critical minerals, energy, and emerging technologies and strengthen key minilateral groupings such as the U.S.-Japan-ROK trilateral, the U.S.-Japan-Australia trilateral, the Quad, and the Squad.
• Japan should bolster its leadership role in sustaining and building minilateral coalitions across a variety of economic and security issues, both in direct collaboration with the United States and in parallel with like-minded U.S. allies and partners, and the United States should welcome these efforts as an additional example of Japan’s burden sharing in support of shared bilateral interests.
   

To ensure their mutual security and prosperity, Japan and the United States should deepen their strategic alignment across core issue areas, including trade and investment, economic security, defense cooperation, and minilateral networking. Implementing alliance priorities will require unprecedented levels of coordination to navigate an increasingly unpredictable global environment.   

Kristi Govella is senior adviser and Japan Chair at the Center for Strategic and International Studies (CSIS) and associate professor of Japanese politics and international relations at the University of Oxford. Nicholas Szechenyi is vice president of the CSIS Geopolitics and Foreign Policy Department and a senior fellow with the Japan Chair.

The authors would like to thank the participants in a series of private roundtables organized by the CSIS Japan Chair program for their candid contributions. Research assistance was provided by Soren Dickson, Gloria Guo, Nana Ida-Nishioka, Christopher Kirch, and Ayla Lunberry.

This brief was made possible by a grant from the Government of Japan.

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