U.S. President Donald Trump (L) and Japanese Prime Minister Sanae Takaichi (R) hold up signed documents for a critical minerals/rare earth deal with Japan during a meeting at Akasaka Palace on October 28, 2025 in Tokyo, Japan. Trump is on a visit to Asia that takes in the ASEAN summit in Malaysia, followed by a trip to Japan and South Korea ahead of the APEC meetings.
Andrew Harnik | Getty Images News | Getty Images
As Japan's Prime Minister Sanae Takaichi travels to Washington for her first summit with U.S. President Donald Trump stateside, the Iran conflict will loom large over their meeting.
The Japanese PM's meeting with Trump on Thursday will be her first after she led the ruling Liberal Democratic Party to victory in February, its largest electoral win since World War II.
Stephen Nagy, professor of politics and international studies at Tokyo's International Christian University (ICU) told CNBC over email that "Takaichi will do what all Japanese PMs do, reaffirm that the Japan-U.S. alliance is the cornerstone of Japan's security but also to the peace and stability of the free and open Indo-Pacific region."
But the topic of Iran is likely to dominate the meeting, experts told CNBC.
Iran conflict
Before the conflict with Tehran started on Feb. 28, Takaichi's meeting was expected to focus on Japan's investment in the U.S., increasing defence spending, and to talk about the now-postponed summit between Trump and Chinese president Xi Jinping. That's according to Jeffery Hornung, Japan Lead for the National Security Research Division at RAND, a U.S. based think-tank.
The original plan was to come "bearing gifts", showing how Japan is a very forward leaning partner in defense and economically, Hornung said in a phone interview. "But the big uncertainty is, how much will the war in Iran dominate the President's thinking on that day?"
"I do think that it would be hard not to talk about having Japan contribute in some capacity, given that it does depend on the Strait for over 90% of its oil imports."
Jeffery Hornung
Japan Lead, National Security Research Division, RAND
In a Truth Social post, the U.S. president called on allies including Japan to help secure the Strait of Hormuz, justifying that it would benefit them more than Washington. So far, no country has publicly committed to support Trump's efforts.
"I'm demanding that these countries come in and protect their own territory, because it is their territory. It's the place from which they get their energy. And they should come and they should help us protect it," Trump said.
Takaichi told Japan's parliament on Tuesday the government is considering what can be done within the framework of Japanese law, although she also said that she would put national interests first, according to public broadcaster NHK.
The Prime Minister's Office also said in a post on X that "There has been no specific request from the United States to Japan for the dispatch of vessels."
Takaichi also reportedly said Monday that there were no plans to dispatch naval vessels to escort boats in the Middle East.
"I do think that it would be hard not to talk about having Japan contribute in some capacity, given that it does depend on the Strait for over 90% of its oil imports," Hornung pointed out.
Under its constitution, Japan's Self-Defense Forces (JSDF) are permitted to use force only to defend Japan.
Since 2015, however, Japan has reinterpreted its constitution to allow limited 'collective self-defense,' enabling the JSDF to assist allies if their attack poses a serious threat to Japan's survival and security.
"Japan as passive support and protector, yes absolutely; but Japan as active leader and possible forward aggressor? That's like asking the sacred Sumo wrestlers to play American football."
Jesper Koll
Expert director, Monex Group
When asked if Tokyo could acquiesce to Trump's request, Hornung said that it would be a high bar, given that Japan has to declare a "survival threatening situation" for the JSDF to use force. Tokyo currently holds the stance that the Iran conflict is not a "survival threatening situation."
ICU's Nagy sees a little more leeway, saying that Takaichi will "skillfully" tip-toe around the issue of sending ships to the Strait. Instead, Japan may agree to refuelling missions or a commitment to diplomacy under Trump's leadership among others.
Should Takaichi agree to deploy Japanese assets to the Middle East, she will have to pay a high price in political capital, according to Jesper Koll, expert director at Tokyo-based financial services firm Monex Group.
Takaichi is very committed to strengthen and modernise Japan to be "America's unsinkable aircraft carrier in Asia," and she enjoys the support of the people in that regard, Koll said in an email to CNBC, but not for Japan to project its strength into the Middle East.
"Japan as passive support and protector, yes absolutely; but Japan as active leader and possible forward aggressor? That's like asking the sacred Sumo wrestlers to play American football," he added.
Investments on the table
Away from the war, Tokyo's investments into the U.S. will also be a topic of discussion. Public broadcaster NHK reported on Wednesday that both sides are "in the final stages of preparations" to announce a joint document outlining a second round of potential investments totalling 11 trillion yen ($69.2 billion) in the U.S.
If so, this will follow the first $36 billion of investments in the U.S., announced in February by Trump and confirmed by Japan.
NHK said the next round of investments will include the construction of next-generation nuclear reactors as well as natural gas power plants.
Under its trade deal agreed in July, Tokyo will invest a grand total of $550 billion into the U.S., in exchange for Trump lowering tariffs on Japanese exports to 15% from 25%. Those tariffs however, have since been struck down by a Supreme Court ruling, with Trump instead imposing 10% global tariffs.
RAND's Hornung said "if [Takaichi] can get something that definitively says that Japan is not going to face any higher tariffs with the different mechanisms that [Trump's] implementing right now, I think that would be seen as a win."
He added that the public in Japan was not supportive of the war, and if Takaichi could head back to Tokyo without committing Japan to the Middle East or being criticised by Trump, "I think that would be a win for her."
English (US) · 