Military Assistance Command, Vietnam
The U.S. Military Assistance Command, Vietnam (MACV) was a joint-service command of the United States Department of Defense, composed of forces from the United States Army, United States Navy, and United States Air Force, as well as their respective special operations forces. MACV was created on 8 February 1962, in response to the increase in United States military assistance to South Vietnam.
Source: Wikipedia — Military Assistance Command, Vietnam (CC BY-SA 4.0)