SEOUL, Aug. 25 -- For the first time in the Ssangyong exercise's two-decade history, South Korean marines will carry out their signature amphibious landing drills without American troops beside them. The reason, Seoul now confirms officially, is that the United States Marine Corps does not have the forces to spare: the Iran war has taken them.

South Korea's Marine Corps said Monday that the United States had notified it in June that the biennial Ssangyong amphibious exercise, scheduled for this September, was being cancelled due to force constraints stemming from the ongoing conflict in Iran. The spokesperson, Han Seung-jeon, said South Korea would conduct its own separate amphibious drills, a quiet acknowledgment that the alliance's sha...