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
North Korea–South Korea relations an explosion at the stern, and was investigating whether a torpedo attack was the cause. Out of 104 sailors, 46 died and 58 were rescued. South Korean President Lee Myung-bak convened an emergency meeting of security officials and ordered the military to focus on rescuing the sailors. On May 20, 2010, a team of international researchers published results claiming that the sinking had been caused by a North Korean torpedo; North Korea rejected the findings. South Korea agreed with the findings from the research group and President Lee Myung-bak declared afterwards that Seoul would cut all trade with North Korea