US Marines cancel major South Korea amphibious drills amid Iran conflict

The U.S. military has canceled its participation in a major amphibious exercise with South Korea next month because forces are constrained by the conflict with Iran, according to the South Korean marine corps.

The U.S. Marine Corps officially notified its South Korean counterpart in June that U.S. force availability for the biennial Ssangyong exercise would be constrained, South Korean marine corps spokesman Lt Col. Han Seung-jeon said at a press briefing Monday in Seoul.

The decision predates President Donald Trump’s order this month to substantially reduce U.S. participation in joint exercises on the Korean Peninsula.

Trump cited the cost of the drills and his relationship with North Korean leader Kim Jong Un in an Aug. 16 Truth Social post directing Defense Secretary Pete Hegseth to scale them back.

The U.S. military subsequently ended its participation Friday in Ulchi Freedom Shield, a major annual summer exercise with South Korea, after five days of a scheduled 11.

Ssangyong is designed to “strengthen interoperability and working relationships across a wide range of military operations - from disaster relief to complex expeditionary operations,” according to the U.S. Marine Corps’ website.

South Korean marines conduct radio checks during a simulated amphibious assault as part of the combined Ssangyong exercise in Pohang, South Korea, Sept. 2, 2024. (Moses S. Lopez Franco/U.S. Marine Corps)

The military uses the term interoperability to describe the ability of a country’s armed forces to use another country’s training methods and military equipment.

Ssangyong was last held Aug. 26 to Sept. 7, 2024, in Pohang, roughly 150 miles south of Seoul.

That training involved about 9,500 U.S. Marines and sailors and 3,500 South Korean troops, along with 20 naval vessels, 30 aircraft and 40 amphibious assault vehicles.

Despite the cancellation, Han pointed to continued cooperation between the allied marine corps through the 2026 Korean Marine Exchange Program and multinational exercises overseas, according to an online video of Monday’s briefing.

Those exercises include Cobra Gold in Thailand, Super Garuda Shield in Indonesia and Rim of the Pacific in Hawaii.

U.S. Forces Korea spokeswoman Choi Min-jung declined to comment on the decision and referred Stars and Stripes to the South Korean briefing.

U.S. Marine Forces Korea spokesman 1st Lt. Benjamin Gillman did not immediately respond Tuesday to a phone call seeking comment.

Trump, during a White House briefing on Aug. 19, described joint exercises with South Korea as “very insulting” to Kim, whom he described as “very well-behaved” during his term.

On Thursday — the next-to-last day of the shortened Ulchi Freedom Shield exercise — North Korea launched approximately 10 short-range ballistic missiles off its eastern coast.