Trials of the Japan-U.S. Alliance: The Strategic Dilemma Posed by Prime Minister Sanae Takaichi's Visit to Washington and the Hormuz Strait Crisis

On March 19, 2026, Prime Minister Sanae Takaichi met with President Donald Trump at the White House in an attempt to reaffirm the Japan-U.S. alliance. However, this visit deviated significantly from the originally anticipated discussions on trade and technological cooperation, becoming dominated by tensions surrounding the U.S.-Iran war and security in the Strait of Hormuz. Amid the clash of two propositions—Japan's strategic autonomy and its alliance obligations—this meeting highlighted the structural challenges facing Japan's security policy.

Initially, Prime Minister Takaichi's visit to Washington was meticulously planned. Following a historic victory for the Liberal Democratic Party in the February general election (which President Trump claimed as his own achievement), the Takaichi administration was in a position to promote deeper alliance ties backed by a strong domestic foundation. Japan had pledged a $550 billion strategic investment fund as part of a trade agreement with the United States, and on February 17, it announced the first phase of projects worth a total of $36 billion, including a natural gas power plant in Ohio, a deep-sea oil export facility in Texas, and a synthetic industrial diamond factory in Georgia. The summit was expected to announce an additional $100 billion in projects, including copper refining and processing, LCD display manufacturing, and nuclear power plants.

In terms of defense, the budget for fiscal year 2026, which passed through the House of Representatives on March 13, included a record $58 billion in defense spending, and on the same day, a bill to establish a National Intelligence Agency was approved by the Cabinet. Japan's defense industry was beginning to grow due to expanded government subsidies and the easing of restrictions on the export of lethal weapons. These developments were supposed to form the basis for the outcomes of the summit, which included deeper information sharing and joint missile production. According to reports, Japan was also expected to express its intention to participate in the Iron Dome missile defense initiative.

However, the outbreak of the U.S.-Iran war overturned all plans. The majority of Japan's oil imports are supplied from the Middle East, passing through the now-closed Strait of Hormuz. On March 15, President Trump urgently requested the dispatch of warships to ensure the security of the strait from several countries, including Japan. This request posed an extremely difficult challenge for Japan. Article 9 of the Japanese Constitution prohibits the use of force except for territorial defense, and the very name of the Self-Defense Forces reflects this constraint.

During the meeting, President Trump told reporters, "Japan is really stepping up," but did not reveal specific details. He also pointed out that much of the oil Japan depends on passes through the Strait of Hormuz, emphasizing, "So there is a big reason to step up." Furthermore, he stated, "Considering the U.S. spending and the number of troops stationed in Japan, I expect Japan to step up. That's the kind of relationship we have," clearly demanding a quid pro quo.

This pressure was significant enough for Kurt Campbell, former Deputy Assistant Secretary of State in the Biden administration and now Chairman of the Asia Group, to comment, "I have never seen such high stakes in a U.S.-Japan summit." Christopher Johnston of the same group noted the possibility that Japan could provide mine-clearing support, but stated, "There is an exceptionally high political hurdle to clear to invoke collective self-defense." In fact, Japan has never invoked collective self-defense.

The Takaichi administration has avoided designating the U.S.-Iran conflict as a "survival crisis situation" (a prerequisite for invoking collective self-defense) and has denied reports that the U.S. State Department officially requested Japan to dispatch warships. Within the Japanese government, there is a view that after combat subsides, the Self-Defense Forces could escort civilian vessels based on the Maritime Security Operations provisions of the Self-Defense Forces Law, but this is fundamentally different from a request to participate in an ongoing war.

Tensions during the meeting were also reflected in a symbolic moment. When asked by a reporter why the U.S. did not notify allies like Japan before attacking Iran, President Trump joked, "I didn't tell anyone. I wanted a surprise attack. Is there a country that knows surprise attacks better than Japan? Why didn't you tell me about Pearl Harbor, huh?" At this moment, Prime Minister Takaichi's slight smile disappeared, and her eyebrows were observed to raise.

From the perspective of energy security, this crisis has serious implications for Japan. An oil supply shock could suppress economic activity, cause inflation to soar, lead to a sharp drop in the yen's value, and disrupt the stock market. This jeopardizes Prime Minister Takaichi's ambitions for strategic autonomy and economic revitalization. The Japanese government has ordered the largest-ever release of strategic oil reserves, but this may be insufficient given the lack of prospects for normalizing oil transport.

Even more serious is the diversion of U.S. military assets to the Middle East, which is weakening deterrence in East Asia. The U.S. has diverted naval vessels stationed in Japan, THAAD missile defense launchers, and approximately 2,500 Marines based in Okinawa to the Arabian Sea. This coincides with a period when China is conducting large-scale exercises around Taiwan. Reports suggest that Prime Minister Takaichi was expected to raise concerns about troop movements during the meeting. Japan views China as an increasing security threat and has been enhancing its military capabilities in the southwestern islands near the East China Sea, precisely at a time when U.S. deterrence is diminishing.

Analysis from the Brookings Institution points out, "As the deterrence issue in East Asia becomes more serious than ever, the likelihood of the U.S. becoming distracted and bogged down in the Middle East is increasing." Prime Minister Takaichi, a hardline conservative who has stated that a Taiwan contingency could qualify as a survival crisis situation for Japan, has made comments regarding military support for Taiwan that heighten tensions with China. Ahead of the planned (now possibly postponed) Trump-Xi Jinping meeting at the end of March, Prime Minister Takaichi aimed to impress upon President Trump how crucial deterrence in the Taiwan Strait is for regional stability. However, the situation is unfolding unfavorably for Japan.

In terms of trade, after the Supreme Court ruled that U.S. tariffs under the International Emergency Economic Powers Act were unconstitutional, the Trump administration is attempting to rebuild tariff leverage. The newly imposed Section 122 tariffs are set at 10% (with the possibility of rising to 15%), which could exceed the 15% cap that Japan secured in its trade agreement with the United States, as these tariffs are added to the "most favored nation" tariffs.

A few days before Takaichi's visit to the U.S., the Office of the U.S. Trade Representative initiated two Section 301 investigations, including Japan. One concerns industrial overcapacity, while the other addresses failures to crack down on imports produced through forced labor. This marks a significant shift from the era when the U.S. and Japan cooperated on these issues. The first Trump administration participated in trilateral work with the European Union to reform international trade rules regarding industrial subsidies and overcapacity. The Biden administration's U.S.-Japan task force has been working to prohibit forced labor in supply chains.

During the Takaichi-Trump meeting, a $40 billion nuclear power plant contract was expected to be announced. U.S. company GE Vernova and Japan's Hitachi are set to construct advanced small modular reactors in Tennessee and Alabama, aiming to stabilize U.S. electricity prices and expand generation capacity. However, this economic achievement is likely to be overshadowed by the turmoil Japan faces on critical fronts of trade, energy, and Indo-Pacific deterrence.

Prime Minister Sanae Takaichi's visit to Washington symbolizes that the Japan-U.S. alliance has entered a new era of trials. The Trump administration's "America First" diplomacy is shaking the traditional foundations of predictability and reciprocity in alliances. Japan is simultaneously facing three strategic challenges: constitutional constraints, vulnerabilities in energy security, and the threat posed by China in East Asia. How the Takaichi administration resolves this complex equation will determine the future direction of Japan's security policy. Whether the goals of deepening the alliance and pursuing strategic autonomy can be achieved without contradiction, or whether a fundamental choice will be forced, remains to be seen in the developments of the coming months.