Korean War two years of fighting became a war of attrition, with the front line close to the 38th parallel. The war in the air, however, was never a stalemate. North Korea was subject to a massive bombing campaign. Jet fighters confronted each other in air-to-air combat for the first time in history, and Soviet pilots covertly flew in defense of their communist allies. The fighting ended on 27 July 1953, when an armistice was signed. The agreement created the Korean Demilitarized Zone to separate North and South Korea, and allowed the return of prisoners. However, no peace treaty was ever signed,
United States in the Korean War Major General John H. Church the head of U.S. field headquarters was confident in the US troop's strengths to push back the North Koreans. On July fifth the troops were finally put to the test when North Korean tanks crept towards Osan. The four hundred infantryman of the U.S. also called Task Force Smith opened fire on the North Koreans at 8:16 am. Only four of the North Korean tanks were destroyed and twenty-nine kept moving forward breaking the US line. At the end of the battle only two more North Korean Tanks and two regiments of North Korean infantry