The Japan–US Summit Meeting and Its Impacts on Japan’s Security Posture

Summary

Prime Minister Sanae Takaichi’s recent summit with US President Donald Trump yielded a range of outcomes. The Brief analyses the reasons why Japan saw the summit as a success. It argues that, beyond the obvious interest in keeping the US invested in the Indo-Pacific region and in Japan’s security, Japan may have seen the summit as an opportunity to buy time for a military build-up and to display ideological alignment with Trump’s objectives in West Asia and beyond.

The Japan–US Summit Meeting

On 18 March 2026, Japan’s Prime Minister, Sanae Takaichi, embarked on a three-day visit to the United States of America for a summit meeting with President Donald Trump.[i] Her visit occurred at a time when the US, along with Israel, was in the midst of offensive operations against Iran. A key background question during her visit concerned the likelihood that Trump would demand Japan’s participation in any effort to ‘open’ the Strait of Hormuz, a demand he had previously made of all transatlantic and transpacific partners.

The summit yielded several outcomes on current issues. On the ongoing conflict in Iran, Takaichi conveyed Japan’s consistent stance that Iran should not be allowed to possess nuclear weapons. She also condemned the closure of the Strait of Hormuz and Iran’s attacks on ‘surrounding areas’.[ii] However, she stopped short of providing military assistance as demanded by the US. Foreign Minister Toshimitsu Motegi, who accompanied the Prime Minister, later told reporters that President Trump ‘listened attentively’ and ‘nodded in agreement’ when she explained that constitutional limitations prevented Japan from deploying military assets to the region.[iii]

In the final statement, the Japanese side restricted itself to calling for an ‘early de-escalation of the situation’. It repeated its traditional boilerplate regarding the need for ‘peace and stability’ in the region. However, a particular sentence at the end of the section on Iran raises an interesting question about Japan’s interest in supporting US priorities. The sentence asserted that ‘we [the two leaders] would like Japan and the United States to work together to expand the production of US-sourced energy, taking into account crude oil procurement needs in Japan and across Asia’.[iv] Unpacking this statement raises intriguing questions: Does Japan intend to supply US crude to Asian markets? Alternatively, does it intend to urge partners to buy US crude (as opposed to, say, Russian crude)? Further developments in this area bear greater scrutiny.

In the Indo-Pacific, Takaichi secured some buy-in from Trump for the Free and Open Indo-Pacific concept. Each of the Quad countries was mentioned as a key node in a ‘network of like-minded countries’, though the word itself remained unmentioned. What is distinctive here is that, while issues relating to China were resolved in one sentence, there was extensive discussion of North Korea-related issues. The Japanese leader apparently sought and received assurances from Trump on continued US commitment to the ‘denuclearisation of the Korean peninsula’ and the resolution of the long-pending abduction issue.[v]

The Summit resulted in the release of four key joint documents. The first, a Joint announcement on Strategic Investment, reviewed the progress of the initial batch of Japanese investments in the US announced in February in fulfilment of the US–Japan trade agreement signed in September last year.[vi] The Joint Statement also announced a new round of projects, comprising Small Modular Reactor construction by a consortium led by GE Vernova and Hitachi in Tennessee and Alabama (costing US$ 40 billion), as well as two natural gas infrastructure construction projects in Pennsylvania (US$ 17 billion) and Texas (US$ 16 billion).[vii]

The second key document was an Action Plan for Critical Minerals Supply Chain Resilience. This document states in its preamble that, due to ‘distortions resulting from pervasive non-market policies and practices’, the critical minerals supply chain remains vulnerable to disruption such as economic coercion. Under the Action Plan, the US and Japan would therefore ‘seek to develop a plurilateral trade initiative in critical minerals supported by price floors or other measures’. The aforementioned initiative would establish price floors, set technical and regulatory standards for extraction and processing, conduct geological mapping, and coordinate stockpiling and actions to counter economic coercion.

Interestingly, under the Action Plan, both countries seek to ‘identify specific mining, processing, and manufacturing projects for critical minerals of mutual interest in the United States, Japan, or third countries, which comply with internationally recognised responsible business conduct standards, and will prioritise financing and other policy support for those projects’. This leaves open the possibility that critical mineral reserves in, say, India could also potentially be subject to the standardisation and pricing measures set up by both countries if these are to be inducted into the supply chain.[viii]

Thirdly, a Joint Fact Sheet for Critical Minerals Project Cooperation was released. This primarily lists key sites for cooperation between the two countries, serving therefore as an addendum to the previous Action Plan. Beyond the US and Japan, Australian projects in Kalgoorlie and Western Australia, graphite mines in Canada and Brazilian lithium extraction projects are listed as potential sites for collaborative exploitation.[ix]

Finally, a Memorandum of Understanding on Deep-Sea Mineral Resource Development was also released. This establishes a new Working Group on Deep-Sea Mineral Resource Development to coordinate scientific research and extraction at sites such as the Japanese Pacific island of Minamitorishima, where a recent survey has found traces of rare-earth minerals in seabed mud. The Working Group is to be co-chaired by a Director-level official from the Japanese MOFA and a Deputy Assistant Secretary-level official from the US Department of State, and its activities are to be reviewed every two years.[x]

Controversies and Factors behind Japan’s Declaration of ‘Success’

As with other bilateral summits, Takaichi’s meeting with Trump saw its share of controversies.[xi] The most prominent one occurred during the press conference in the Oval Office before the summit, when a question by a Japanese reporter regarding the lack of prior consultation with European and Asian allies before the Iran attack prompted Trump to make a disparaging remark about Imperial Japan’s attack on Pearl Harbour in 1941.[xii]

The Japanese government nevertheless declared the summit a ‘success’.[xiii] The reasons for this self-declaration need some excavation, as they strike at the very heart of Japan’s objectives for the maintenance of the US–Japan alliance.  Four justificatory factors may be identified here. The first factor to keep in mind is that Japan approached the meeting with the obvious objective of keeping the US engaged in the Indo-Pacific region.[xiv] This goal was largely achieved by Trump’s endorsement of FOIP and of collaboration with like-minded countries such as the ROK, the Philippines, Australia and India.[xv] The DPRK’s potent challenge to Japan was also addressed.

A second, equally self-evident, factor is the Japanese desire to keep the US invested in its defence. Takaichi’s predecessor, Shigeru Ishiba, had managed to secure from Trump a guarantee that the US’ extended nuclear deterrence ‘umbrella would apply to the disputed Senkaku Islands in the East China Sea’.[xvi] Japan would obviously have been anxious to retain this commitment, especially in light of increased Chinese activity around the islands. Again, ongoing changes within the structure of the US forces stationed in Japan, with special focus on the recently effected elevation of the US Forces in Japan to an independent command structure headed by a three-star US Air Force general officer, would also have been a top priority for Japanese defence planners.[xvii]

On the economic security front, too, though the Strategic Investment plan is itself the outcome of US coercion via Trump’s tariffs, in Japan’s case, it may best be characterised as ‘coercion with consent’. This is because the agreements emerging from the summit offer tangible opportunities for Japan to shift its dependencies away from China towards the US and keep the US ‘on-side’ economically.[xviii] However, apropos of the Pearl Harbour reference, there is a significant risk of Japan ending up replicating the ‘1941 problem’ that precipitated the attack in the first place.[xix]

Two less-obvious factors could also lie behind Japanese satisfaction with the summit’s outcomes. The first is that the continuation of security cooperation may have bought Japan time to build up its domestic defence capabilities. The Japanese defence build-up continues to require significant time, resources and assistance from the US, especially in highly technical fields where Japan is still developing competencies.

Four examples exemplify this dependency. In the maritime domain, Japan deployed an Aegis-class destroyer capable of firing Tomahawk cruise missiles in March.[xx] If more such vessels are to be deployed, significant US assistance would be required to retrofit the vessels accordingly. In ballistic missile defence, US permissions necessary to procure advanced laser seekers for use in the PAC-3 Patriot missile batteries were granted on 2 April, enabling PAC-3 production in Japan to take off further.[xxi]

Simultaneously, the US has also allowed Japan to move forward with the development of the newly designated Type-25 Hyper Velocity Glide Projectiles on 31 March, giving a fillip to Japanese efforts to deploy an indigenously made hypersonic glide vehicle.[xxii] In the ground realm, the continuous unfolding of the USFJ’s ‘distributed lethality’ doctrine across Japan’s vital southwestern islands (Nansei Shoto) requires tight cooperation between the US Marine Corps and the Japanese Ground Self-Defence Forces.[xxiii] Finally, Japan may also seek US assistance (whether through AUKUS or independently) to build, train and manage nuclear-powered submarines, a goal its political leadership has already committed to pursuing proactively.[xxiv]

Finally, it may be argued that Japan’s current leaders possibly feel a sense of ideological alignment with Trump’s objectives in Iran. Not only are Japanese archconservatives (of whom Takaichi is one) inveterately pro-US, but there is a dominant element of policymakers in the foreign and defence ministries, known as the ‘American School’, that believes that Japan must always strive to be in perfect synchronisation with US interests to maintain the post-1945 order in East Asia.[xxv] Thus, though they have adroitly avoided explicit elucidations of their stance on the legality of the US and Israel’s actions in Iran, and they continue to maintain close and cordial relations with Tehran, Japanese policymakers, especially on the far right, may not be entirely opposed to the capricious and unilateral display of US power demonstrated by Trump.

Israel’s role in this conflict would also be noteworthy, as its actions clearly demonstrate that a strategic ally can plausibly invest the US in a regional conflict if the incumbent of the Oval Office is convinced that the former shares his objectives and antipathy towards a common ‘opponent’. In light of the ‘Taiwan panic’[xxvi] currently emerging in Japan after Takaichi’s November statement in the Diet, it may not strain credulity to believe that a section of policymakers may be hoping that American caprice and bullishness may keep China sufficiently uncertain of its intentions as to deter any decisive move towards Taiwan.

Implications of Japan’s New Security Posture

In the 1980s, some Japanese policymakers and intellectuals believed that Japan could ‘say no’ to the US because its economic strength created a dependency that Washington could not reverse without inflicting significant pain on its own economy. It is ironic, therefore, that the ‘worsening regional situation’ identified by Japanese strategists and policymakers has created circumstances whereby Japan is now perceived as the ‘country that can’t say no’ to the US, its only security guarantor.[xxvii]

The implications of this unwillingness to resist US demands require cautious observation. Should present trends continue, and Takaichi (or those who share her worldview) remain in power, it is almost certain that Japan will continue to pursue tighter alignment with the US, which may extend to suborning its freedom of action to Washington. Indeed, it cannot be disavowed that Takaichi or her successors may end up pursuing Constitutional revision to better comply with US prerogatives.

This could be especially relevant in case of a Taiwan contingency, where Japanese policymakers could well choose, as per a four-fold schema proposed by a noted scholar of Japanese security and international relations, a ‘spearhead’ role by utilising Japanese military assets to invest the US in the crisis, especially if the latter’s commitments to Taiwan’s security are perceived to be wavering or uncertain of being delivered.[xxviii]

The key challenge for Japan in this scenario would be to avoid hewing so closely to the US that it is universally perceived as doing its bidding. This would be especially damaging to Japan’s self-cultivated aspiration to act as a ‘bridge between the Global North and Global South’, particularly if Japanese armed forces are deployed in the service of US objectives in unpopular ways.[xxix]

Views expressed are of the author and do not necessarily reflect the views of the Manohar Parrikar IDSA or of the Government of India.

[i] “Prime Minister Takaichi’s Visit to the U.S. (March 18-21, 2026)”, Ministry of Foreign Affairs, Government of Japan, 19 March 2026.

[ii] “Japan-U.S. Summit Meeting and Dinner Reception”, Ministry of Foreign Affairs, Government of Japan, 19 March 2026.

[iii] Takashi Ogawa and Sotaro Hata, “Takaichi Tells Trump Article 9 Limits Japan’s Role in Iran war”, The Asahi Shimbun, 23 March 2026.

[iv] “Japan-U.S. Summit Meeting and Dinner Reception”, no. 2.

[v] Ibid.

[vi] Ibid.

[vii] Observers of American politics will realise that the locations cited are all key electoral swing states and/or centres of Trump’s support base.

[viii] “Japan-U.S. Summit Meeting and Dinner Reception”, no. 2.

[ix] Ibid.

[x] Ibid.

[xi] Aside from the Pearl Harbour reference discussed below, there were other controversies as well. See Julian Ryall, “Japan PM Mocked as ‘Trump Sycophant’ After Giggling at Biden’s Autopen Portrait”, South China Morning Post, 24 March 2026.

[xii] Toshiyuki Ito, “Takaichi’s Summit Success: March Meeting with Trump Ends ‘Without Incident’”, Nippon.com, 27 March 2026.

[xiii] Ibid.

[xiv] Ryo Sahashi, “Japan’s Security Policy is Still Caught Between the Alliance and Domestic Reality”, Commentary, Carnegie Endowment for International Peace, 27 March 2026.

[xv] Yuichi Hosoya, “Diplomacy Key as FOIP Vision Gains Significance”, The Japan News by the Yomiuri Shimbun, 3 April 2026.

[xvi] “Japan-U.S. Summit Meeting”, Ministry of Foreign Affairs, Government of Japan, 7 February 2025.

[xvii] Todd South, “Pentagon Splits Combined US Forces Japan Forces and 5th Air Force into Two Commands”, Air & Space Forces Magazine, 26 March 2026.

[xviii] Ryo Sahashi, “Japan’s Security Policy is Still Caught Between the Alliance and Domestic Reality”, no. 14.

[xix] Scholars widely believe that US embargoes on essential raw materials such as iron and oil (in retaliation for Japan’s invasion of China in 1937) led Japanese military planners to decide to attack the US pre-emptively before resource constraints could tie their hands. An excellent overview is provided in “Pearl Harbor Attack”, Encyclopedia Britannica, 21 March 2026.

[xx] Dzirhan Mahadzir, “Japanese Aegis Destroyer Completes Modifications to Operate U.S.-made Tomahawk Missiles”, USNI News, 27 March 2026.

[xxi] “Department of War Forges Landmark Agreement to Triple PAC-3 Seeker Production, Bolstering the Arsenal of Freedom”, Department of War, Government of the United States of America, 1 April 2026.

[xxii] Mike Yeo, “State Department Clears $340M FMS Request for Hypersonic Missile Testing Support for Japan”, Breaking Defense, 27 March 2026.

[xxiii] Dan Goure, “Is Japan the Key to U.S. Military Strategy in the Pacific?”, The National Interest, 31 October 2021.

[xxiv] Kosuke Takahashi, “Japan’s Nuclear Submarine Debate Gains Momentum Amid Rising Pacific Threats”, The Diplomat, 29 January 2026.

[xxv] Leo Lewis and Demetri Sevastopulo, “The Country That Can’t Say No to Trump”, Financial Times, 10 April 2026.

[xxvi] A good example of this is Kolas Yotaka, “Japan is Preparing for the Worst. Taiwan is Just Preparing Excuses”, Nikkei Asia, 31 March 2026.

[xxvii] Leo Lewis and Demetri Sevastopulo, “The Country That Can’t Say No to Trump”, no. 25.

[xxviii] Stephen Nagy, “The Day Deterrence Fails in the Indo Pacific”, Commentary No. 165, The Japan Forum on International Relations, 9 April 2026.

[xxix] Toshiyuki Ito, “Takaichi’s Summit Success: March Meeting with Trump Ends ‘Without Incident’”, no. 12; Ryo Sahashi, “Japan’s Security Policy is Still Caught Between the Alliance and Domestic Reality”, no. 14.usa