Walton Walker backed South Korea, and China allied with the Soviet Union in what was to become the first military action of the Cold War. Shortly after 75,000 North Korean troops with tanks invaded South Korea on June 25, 1950, American air and sea forces were ordered by President Harry S. Truman to give South Korean troops support. The U.S. Eighth Army was ordered to intervene and drive the invaders back across the 38th parallel, the border between the two countries. With only four lightly equipped and poorly trained divisions, Walker began landing troops on the southeast side of the Korean peninsula
South Korea in the Vietnam War United States as a foreign army. Economic payment in return for the participation of Korea was an underlying cause for its participation, with a House Subcommittee hearing chaired by J. William Fulbright criticising the deployment of Korean forces as resembling the "hiring of mercenaries". Participation in combat was directly linked to monetary compensation, and during the Vietnamization period Park Chung-hee demanded further compensation in order for South Korea to take a more direct combat role, which the US was unwilling to do. South Korea at the time was alarmed by the United States' plan to move two of its military