Japan and South Korea Watch Trump-Xi Summit Through Taiwan, North Korea and Hormuz (2/4)

Japan and South Korea are watching the Trump-Xi summit through Taiwan, North Korea, and the Strait of Hormuz as America’s Indo-Pacific allies test whether Washington can manage competition with Beijing without weakening deterrence or alliance confidence.

By Ahmed Fathi

New York, NY: Tokyo and Seoul will closely watch President Donald Trump’s planned summit with Chinese President Xi Jinping in Beijing. For Japan and South Korea, the meeting is not only about China. It is about Taiwan, North Korea, energy security, and the future of America’s alliance system in the Indo-Pacific.

Both countries want U.S.-China tensions managed. Neither wants a crisis between the world’s two largest powers. But both will look for signs that stability with Beijing is not being bought through softer language on Taiwan, weaker pressure on North Korea, or uncertainty over U.S. commitments.

Japan’s first concern is Taiwan. A crisis across the Taiwan Strait would affect Japanese territory, U.S. bases in Japan, sea lanes, and the East China Sea. Tokyo has publicly supported stable U.S.-China relations, but its real test is whether Washington keeps deterrence clear and allies fully briefed.

China’s view is different. Beijing presents the summit as a chance to stabilize relations, but it continues to treat Taiwan as a core sovereignty issue. For Japan, that means every word in the U.S. and Chinese readouts will matter. A vague phrase in Beijing can become a security concern in Tokyo.

South Korea reads the summit through North Korea. Seoul depends on the U.S. alliance, trades heavily with China, and faces a nuclear-armed neighbor that is hardening its position. North Korea has moved further away from any serious denuclearization track, while portraying U.S.-Japan-South Korea cooperation as a hostile military bloc.

That makes any Trump-Xi discussion of the Korean Peninsula sensitive. If Trump seeks Chinese help on North Korea, Seoul will want to know the price. It will also want to avoid being sidelined by another leader-level channel that treats South Korea as an observer of its security.

Then comes Hormuz.

Japan and South Korea are advanced industrial economies with a simple vulnerability: much of their energy comes from the Gulf. Japan relies on the Middle East for around 95% of its oil supplies, and about 70% of its oil imports normally pass through the Strait of Hormuz. South Korea also faces exposure. More than 60% of its crude imports and about half of its naphtha imports passed through Hormuz in 2025, according to AP. (AP News)

That makes Iran part of the Northeast Asian story. South Korea recently condemned an attack on a cargo ship operated by HMM near the Strait of Hormuz, while Trump has pressed Seoul to support U.S.-led efforts to protect maritime routes in the region. (Reuters) Japan and the United Arab Emirates have also discussed expanded oil supplies and joint crude stockpiles as Tokyo investigates how to reduce exposure to disruptions.

So when Trump discusses Iran with Xi, Tokyo and Seoul will listen closely. China has ties with Tehran and major energy interests in the Gulf. If Beijing helps calm the crisis, Japan and South Korea benefit. If China uses its role to seek concessions elsewhere, the Middle East file becomes an Indo-Pacific problem.

The alliance issue sits above all of these considerations.

Japan and South Korea are not side players in U.S. strategy. They are the anchors of America’s military posture in Northeast Asia. U.S. forces in both countries support deterrence against China and North Korea and help Washington project power across the Indo-Pacific.

Trump’s transactional view of alliances has already made allies more careful. Tokyo and Seoul can manage pressure to spend more on defense. What they cannot easily manage is uncertainty over whether Washington sees alliances as long-term strategic commitments or negotiable costs.

That is why the best outcome for Japan and South Korea is not dramatic. It is disciplined: clear U.S. language on Taiwan, no weakening of deterrence against North Korea, practical movement to keep Hormuz open, and reassurance that alliances remain central to U.S. strategy.

The worst outcome is also clear: a summit that produces headlines in Washington and Beijing but leaves America’s allies guessing about what was quietly traded.

This is the second article in an ATN series examining the global stakes of Trump’s China visit. The first looked at Taiwan, Iran, and the broader U.S.-China power contest. The next pieces will examine how the Middle East and North Africa are reading the summit through Iran, oil, and strategic hedging, and how Europe is watching Ukraine, trade, NATO, and China policy.

For Japan and South Korea, the Trump-Xi summit is not one story. There are four: Taiwan, North Korea, Hormuz, and the future of the U.S. alliance system in the Indo-Pacific. Any one of them can shake the region. Together, they explain why America’s allies will listen carefully not only to what Trump tells Xi but also to what he tells them after Beijing.

**About the Author: Ahmed Fathi is an internationally syndicated journalist, United Nations correspondent, global affairs analyst, and human rights commentator. He writes about diplomacy, multilateralism, power, public freedoms, and the politics shaping our global future.