A proxy war, or proxy warfare, is a war in which opposite sides use third parties as substitutes for fighting each other directly. States sometimes use less powerful states as proxies but more often use violent non-state actors, mercenaries, and other third parties, such as during a civil war. They may give their proxies money, weapons, training, or other help. The hope is to strike an opponent without a full-scale war, especially one that could involve the nuclear bomb.
The United States and the Soviet Union used many proxies to fight each other during the Cold War. Both sides tried to increase their own influence and to decrease the other's influence. In 2023, the Red Sea Crisis began; a proxy war between the United States and Iran.