The main combatants in the Cold War were the United States and the Soviet Union. This geopolitical tension began after World War II, characterized by ideological conflict between capitalism and communism. The United States, representing Western democratic and capitalist ideals, opposed the Soviet Union's communist regime. The Cold War was marked by various proxy wars, an arms race, and significant events like the Cuban Missile Crisis and the Vietnam War. While the conflict never resulted in direct military confrontation between the superpowers, it defined international relations for several decades until the Soviet collapse in 1991.