Moore was admitted to the United States Military Academy at West Point, New York, on the recommendation of outgoing Democratic U. S. Representative Albert Rains, and after confirmation of that nomination by incoming Republican Representative James D. Martin of Gadsden. He graduated in 1969 with a Bachelor of Science degree. With the Vietnam War underway, Moore served in several posts as a military police officer, including Fort Benning, Georgia, and Illesheim, Germany before being deployed to the Republic of Vietnam. Serving as the commander of 188th Military Police Company of the 504th Military Police Battalion, Moore was perceived to be reckless, but very strict. He insisted his troops salute him on the battlefield, against his training, as such recognition facilitates an officer being targeted by an enemy. Some of his soldiers gave him the derogatory nickname "Captain America", due to his attitude toward discipline. This role earned him enemies, and in his autobiography he recalls sleeping on sandbags to avoid a grenade or bomb being tossed under his cot, as many of his men had threatened him with fragging.