U.S. President Donald Trump warned that allies who do not comply with his demand to dispatch warships to the Strait of Hormuz will face consequences, saying he would "never forget." On the 26th, Trump said he was "deeply disappointed" that "NATO did nothing to help U.S. military operations against Iran," singling out Germany, the United Kingdom and Australia for criticism. While South Korea was not mentioned, there are concerns that Trump may use the issue as leverage in trade and security negotiations with Seoul after the Iran conflict is settled. U.S. Secretary of State Marco Rubio also signaled the same day that Washington would reconsider its support for the Ukraine war if NATO continues to be uncooperative on the Iran conflict. The Western collective security framework, which has endured for roughly 80 years, now faces a crisis of fracture due to the Iran war.
Trump indicated he would extend the moratorium on strikes against Iranian power plants by another 10 days, while also hinting at a "final blow" that could include the deployment of ground troops. Analysts say the next 10 days will be a critical turning point that determines the course of the Iran war. Iran is attempting to drive a wedge between South Korea and the United States. The Iranian ambassador to South Korea said the same day that "Korean ships conducting transactions with the United States will have difficulty passing through the Strait of Hormuz." South Korean refiners are deeply intertwined with the United States through ownership structures and trade, raising serious concerns that Korean vessels could face prolonged isolation from the strait. This is the moment for Seoul to exercise sophisticated diplomacy to avoid being trapped in a binary choice between the United States and Iran.
The possibility cannot be ruled out that the Trump administration will move to reorganize alliances by distinguishing "who is truly on America's side" and applying differential treatment accordingly. U.S. allies facing growing diplomatic and security burdens are rushing to form multinational coalitions, primarily centered on Europe. The idea is to demonstrate goodwill toward Washington — not by participating in military operations, but by dispatching forces for post-war defensive missions such as escorting merchant ships and tankers or clearing mines. South Korea has also attended a multinational military meeting at France's request. However, as the Strait of Hormuz is a lifeline for South Korea's economy, the country needs to pursue more proactive communication with allies and explore international cooperation measures. Any intervention in the Iran crisis should preferably take place within the framework of a UN Security Council resolution or multilateral cooperation. Only then can South Korea protect its national interests while minimizing conflict with Iran and damage to the U.S.-South Korea alliance.