The Kremlin controlled the socialist states that it established in the parts of Eastern Europe its army occupied in 1945. After eliminating capitalism and its advocates, it linked them to the USSR in terms of economics through COMECON and later the military through the Warsaw Pact. In 1948, relations with Yugoslavia disintegrated over mutual distrust between Stalin and Tito. A similar split happened with Albania in 1955. Like Yugoslavia and Albania, China was never controlled by the Soviet Army. The Kremlin wavered between the two factions fighting the Chinese Civil War, but ultimately supported the winner, Mao Zedong. Stalin and Mao both supported North Korea in its invasion of South Korea in 1950. But the United States and the United Nations mobilized the counterforce in the Korean War (1950–53). Moscow provided air support but no ground troops; China sent in its large army that eventually stalemated the war. By 1960, disagreements between Beijing and Moscow had escalated out of control, and the two nations became bitter enemies in the contest for control of worldwide communist activities.