United Nations and American Involvement
Washington got word of the invasion from Jack James' UPI dispatch, which arrived before the official cable to the State Department. President Harry Truman and the United Nations, which had supervised the elections in South Korea, were notified. Trygve Lie, Secretary General of the U.N., declared, "This is war against the United Nations."
President Truman ordered Five-Star General Douglas MacArthur, U.S. Commander in the Far East, headquartered in Tokyo, to provide logistical support for the ROKs while the U.N. called for withdrawal of North Korean troops. When this appeal was ignored, the U.N. called for its members to ". . . furnish such assistance to the Republic of Korea as may be necessary to repel the armed attack and to restore international peace and security to the area." Truman ordered U.S. naval and air forces to assist the ROKs. After a personal reconnaissance revealed the plight of the ROK troops, General MacArthur advised that only U.S. ground troops could halt the invasion. These were ordered to Korea on June 30th by the President, his most difficult decision while in office.
Although excluded from the American perimeter of defense, General Omar Bradley noted in a 1948 meeting of the National Security Council that some moral obligation did exist since the Republic of Korea was an American creation. It was decided that one possible way to save South Korea, should it be invaded, would be by a United Nations "police action" to which the U.S. could contribute troops.
The bulk of the U.N. forces to serve in Korea would be American, whose peak strength reached 348,000. Altogether 5.7 million were in uniform during the period, while 1.5 million were rotated in and out of Korea. Battle deaths for the three-year period numbered 33,627 as compared to 47,367 for the ten-year Vietnam War. Combat deaths in Korea by service were: Army 27,704; Marines 4,267; Air Force 1,198; Navy 458.
Other countries to furnish combat units, with their peak strength, were Australia (2,282), Belgium/Luxembourg (944), Canada (6,146), Colombia (1,068), Ethiopia (1,271), France (1,119), Greece (1,263), Netherlands (819), New Zealand (1,389), Philippines (1,496), Republic of South Africa (826), Thailand (1,294), Turkey (5,455), and the United Kingdom (Great Britain 14,198).
Medical units were furnished by Denmark, India, Italy, Norway, and Sweden.
The Republic of Korea's armed forces reached a strength of 590,911 and suffered 272,975 casualties--killed, wounded, missing. Korean civilian deaths, both North and South, have been estimated to have been over 2 million.
Both the U.N. and ROK troops were placed under command of General MacArthur. For the first time in history, a world organization would use force to stop military aggression.
During World War II, President Franklin Roosevelt had asked the leader of the Soviet Union, Joseph Stalin, to enter the war against Japan. Stalin said he would two or three months after Germany's surrender. He could hardly refuse. The U.S. and Great Britain had shipped, free of charge, huge quantities of war supplies, including almost 500,000 American-made trucks and jeeps to the Soviets, which enabled them to stave off a defeat by the Germans during the early part of the war.
The Germans surrendered in May 1945. By August, the Soviets were trying to obtain more concessions and incentives for entering the war against Japan. The U.S. refused because Japan was on the verge of collapse and Russian help was not needed. The first atomic bomb was dropped on august 6 and the second bomb was dropped on August 9, the same day the Soviets declared war on Japan. The Japanese surrendered on August 14, 1945, five days later.
The Soviet failure to conduct free and open elections, in accordance with the Yalta agreements, in Poland and other eastern European countries, which they had overrun, had aroused U.S. suspicion and had sown the seeds for the cold war. As their troops moved into Korea, which the Japanese had annexed in 1910 and harshly occupied, the U.S. contacted Moscow and asked them to accept surrender of the enemy troops above the 38th parallel, which the U.S. would do south of that line. The Soviets agreed. Japan traditionally had regarded the Korean Peninsula as a dagger pointing at their country.