Japanese Prime Minister Sanae Takaichi will be the first U.S. ally to visit the White House since President Trump requested assistance in sending ships to patrol the Strait of Hormuz. Although Trump later said the United States does not need help, Takaichi faces pressure to balance pleasing the U.S., Japan’s only treaty ally, with legal and political limits at home.
Takaichi has stated Japan has no plans to dispatch warships to the Middle East but has not explicitly rejected Trump’s appeal. Ahead of the White House meeting she told lawmakers she would “clearly explain what we can do and cannot do based on the Japanese law.”
Japan’s constitution renounces the right to wage war, and domestic law tightly constrains overseas military action. In 2015 Tokyo reinterpreted its constitution to allow limited collective self-defense—permitting deployment of the Self-Defense Forces (SDF) if Japan or its allies face a “survival-threatening situation”—but that framework still restricts combat roles.
Takaichi has avoided ruling on the legality of the U.S.-Israeli attack on Iran; declaring it preemptive or unprovoked could undercut the legal rationale for deploying the SDF. Public opinion also weighs heavily: a recent Asahi Shimbun poll found 82% of Japanese oppose the war in Iran and more than half disapprove of Takaichi’s reluctance to speak about it, even as she remains popular and pushes for higher defense spending.
Past Japanese governments have sought compromises when asked to support overseas operations. Tokyo has found legal workarounds — sending minesweepers to the Persian Gulf in 1991, noncombat troops to Iraq in 2004, and a destroyer and patrol plane to the Gulf of Oman in 2020 — while requiring forces to avoid active combat zones. Critics warn that escorting tankers through the Strait of Hormuz during an ongoing war could be far more serious, potentially amounting to entering a state of war with Iran.
Former defense official Kyoji Yanagisawa, who helped plan Japan’s Iraq deployment and later became a critic of military expansion, cautions that SDF involvement that led to casualties would be unprecedented. He notes the SDF completed its Iraq mission without firing a shot or suffering casualties, and he wants that record preserved. Takaichi, by contrast, advocates expanding the SDF’s offensive capabilities.
Takaichi’s visit was timed to precede President Trump’s planned trip to China, with hopes she could influence U.S. handling of Tokyo’s disputes with Beijing over issues such as Taiwan, or at least safeguard Japanese interests if Trump reaches an agreement with Xi Jinping. But the Iran war prompted Trump to postpone his Beijing trip, and the conflict threatens to overshadow other agenda items—including Japan’s pledged $550 billion investment package in the U.S., offered in part to secure lower American tariffs.
As Takaichi meets Trump, she must navigate U.S. expectations, Japan’s legal constraints, fragile public support for involvement, and the wider diplomatic fallout of a regional war that is reshaping Washington’s plans and Tokyo’s priorities.
