The United States entered the Second World War in 1941 not to conquer but to liberate a world falling to tyranny. Sixteen million served in uniform, more than 400,000 lost their lives, and many millions supported the war effort on the home front, while families bore the price of service as blue stars in windows were too often replaced by gold stars marking loss. Only five years after World War II ended, the United States entered another major international conflict when North Korea attacked South Korea on June 25, 1950. Troops from Japan joined those already in Korea and fought with other nations under the U.N. flag in what became a prolonged and bitter three-year war. In 1953 a negotiated settlement restored an uneasy peace and established a new boundary near the original one at the 38th parallel. One-and-a-half million American men and women served in Korea in combat and support roles, many performed extraordinary acts of heroism, and 131 received the Congressional Medal of Honor. Those who answered the call defended a country they never knew and a people they never met, reflecting the belief that freedom is not free.