Iran–Iraq War
After the war started (especially between 1983 and 1988), the United States sold weapons to the Iraqis. This move was mainly due to America's interest in containing the revolutionary Ayatollah Khomeini. Thus, both the Soviet Union and the United States supplied Iraq with weapons against Iran. The United States had sold many weapons to Iran before the war. It was believed the Soviet Union was selling weapons to both sides during the war.