The 1st Marine Expeditionary Force (1st MEF) is a major formation of the United States Marine Corps, primarily based at Marine Corps Base Camp Pendleton in California. It is designed to be a rapid-response force capable of conducting a variety of military operations, including amphibious assaults, humanitarian assistance, and combat missions. The 1st MEF is composed of ground, air, and logistics units, allowing it to operate independently in diverse environments. Established in 1941, the 1st MEF has participated in numerous conflicts, including the Vietnam War and the Gulf War. It plays a crucial role in the U.S. military's ability to project power and respond to crises around the world. The force is often deployed in support of U.S. Central Command and other military operations, showcasing the versatility and readiness of the Marine Corps.