Seoul must guard deterrence if USFK assets move

South Korea and the United States are in consultations over the possible redeployment of some U.S. Forces Korea assets to the Middle East as the war between the United States and Iran continues. On Wednesday, the South Korean government said it would not comment on operational matters involving U.S. Forces Korea but confirmed that Seoul and Washington are maintaining close communication. Military assets that could potentially be sent to the Middle East include air defense systems such as ATACMS tactical surface-to-surface missiles, Patriot PAC-3 interceptors and the THAAD missile defense system.

Discussions between Seoul and Washington are understood to focus primarily on the urgent demand for ground strike missiles and air defense interceptors should the war drag on. Large-scale airstrikes against Iran and Iranian retaliatory attacks have already intensified air defense operations, raising concerns about shortages of strike and interception equipment as well as ammunition depletion. During the war in Ukraine, the United States also struggled to replenish Kyiv’s ammunition stocks and even relied on indirect artillery support from South Korea.

The deeper concern is that the conflict appears increasingly likely to expand and evolve into a prolonged war. The United States has effectively entered a proxy ground conflict by backing Kurdish rebel forces, while Iran is reinforcing its resolve to continue fighting. After the death of Supreme Leader Ali Khamenei in an explosion, Tehran designated his son, the hardline figure Mojtaba Khamenei, as his successor. Wars are often easier to begin than to end. If the United States becomes mired in a prolonged conflict, the redeployment of U.S. Forces Korea assets could expand from ammunition transfers to the movement of equipment and even personnel.

Any diversion of U.S. Forces Korea assets would inevitably weaken deterrence against North Korea and could risk encouraging miscalculation in Pyongyang. At the same time, North Korean leader Kim Jong Un recently observed the test launch of strategic cruise missiles from a new destroyer. Kim has already used the war in Ukraine as an opportunity to strengthen his regime’s strategic position. The ongoing war in the Middle East could similarly embolden North Korea to pursue further adventurism.

Seoul and Washington have long emphasized the principle that whenever U.S. Forces Korea assets are redeployed elsewhere, replacement capabilities will be deployed to ensure that the combined defense posture remains intact. Thorough contingency measures are essential to prevent any gap in deterrence against North Korea. Moreover, these discussions carry additional significance because they come after the two allies agreed last year on the “modernization of the alliance.” The outcome could set an important precedent for the future strategic flexibility of U.S. Forces Korea. Careful and meticulous coordination between the two governments is therefore more necessary than ever.