North Korea was a communist country and South Korea was not. As usual, we. (the U.S.A.) had to prevent the North from dominating the South, so we sent our troops there to help the South Koreans. The Russians and the Chinese also had troops and planes helping the North Koreans, because they too were Communists. It was not called a war; it was called a "police action" and it lasted from 1950-53. There was never an end to the "war"; we just agreed to a cease fire and there are still about 35,000 U.S. servicemen still. stationed there. The 38th parallel is the agreed. upon Truce Line. The total amount of U.S. servicemen killed or wounded in action may never be known, but I think over 50,000 were killed and more than that were wounded. We still have hundreds unaccounted for who are. now referred to as missing in action. (M.I.A.'s)