Which part of Vietnam and Korea did the US support?

During the Vietnam War, the United States supported South Vietnam, officially known as the Republic of Vietnam, in its fight against the communist North Vietnam, backed by the Soviet Union and China. In the Korean War, the US supported South Korea, officially the Republic of Korea, in its defense against the communist North Korea, which was backed by China and the Soviet Union. This support was part of the broader strategy of containment during the Cold War to prevent the spread of communism in Asia.