<P> At the conclusion of World War II the Allied nations began the process of disarmament of Axis controlled regions . Japan occupied Korea at this time and had been in control since 1910 . In 1945, the decision was made to have American Marines forces oversee Japanese surrender and disarmament south of the 38th parallel and the Soviet Union would facilitate the change of power to the north . At the time there was no political motivation and seemed to be a logical and convenient plan of action . The original agreement and intent was to create a unified and independent Korea out of the post Japanese occupation era . Instead each side of the 38th parallel established its own government under the influence of the occupational country; the United States in South Korea and the Soviet Union in North Korea . Both new Korean governments discredited the other and claimed to be the only legitimate political system . Tensions between the North and South escalated and each side began to petition foreign powers for resources and support . South Korea wanted weapons and supplies from Truman and the United States government while North Korea sought help from Stalin and the Soviet Union . The United States was still war weary from the disruptive World War II campaign and refused South Korea's request for weapons and troops . North Korea convinced the Soviet Union to supply them with the weapons and support they requested . This decision coincided with the United States withdrawing the last remaining combat troops from South Korea . North Korea saw its opportunity and attacked South Korean forces at the 38th parallel on June 25, 1950 and thus initiating the Korean War . </P> <P> In response to North Korea's invasion into South Korea the United Nations convened to formulate a response . The U.N. demanded North Korea's immediate withdrawal and, when this was not met, United States Army General Douglas MacArthur was appointed supreme commander of U.N. forces . To halt the rapid progress of North Korean forces into the south Task Force Smith was deployed to the Korean front from Japan . Task Force Smith consisted of U.S. Army officers and regiments of the Army's 24th Infantry Division that were stationed in Japan as occupational forces . Unfortunately the 24th were under trained, poorly supplied, and outnumbered . The 24th offered very little resistance against the North Korean advance . American and South Korean troops were pushed south and in late July 1950 Task Force Smith was overrun in the city of Taejon . Troops from the Army's 25th Infantry Division were deployed to Taejon to establish a new line and pullout the decimated 24th I.D. This addition of combat troops did not stop the North Korean advance and both American and South Korean troops were pushed further south . </P>

When was the us involved in the korean war