During the Cold War, the United States and Soviet Union avoided direct military conflict by engaging in proxy wars where they supported opposing sides in regional conflicts. The document discusses several Cold War proxy wars including the Greek Civil War, Korean War, Vietnam War, Bay of Pigs Invasion, Chilean Coup, Angolan Civil War, and Soviet-Afghan War. In each conflict, one superpower backed one side while the other supported the opposition, deepening tensions between the US and Soviet Union.