First Lieutenant George K. Sisler received the Medal of Honor, posthumously, at the age of 30. However, reading his biography, it seems as if this officer was destined to be a hero. Born in 1937 in Dexter, Missouri, he served in the Army National Guard for a year in 1956-57, and then the Army Reserves from 1957-58. He then enlisted in the Air Force from 1958 to 1962, and in the Regular Army from 1964 to 1965. After Officer Candidate School, he was commissioned as a Second Lieutenant on 22 June 1965. As a First Lieutenant, Sisler served in Headquarters Company, 5th Special Forces Group (Airborne), First Special Forces, Vietnam. At the time, he was the Assistant Intelligence Officer (G-2).

While serving as the platoon leader/advisor to a Special United States/Vietnam exploitation force, on patrol deep within enemy dominated territory, 1LT Sisler's platoon was attacked from three sides by a company-sized enemy force. He quickly rallied his men, deployed them to a better defensive position, called for an air strike, and moved among his men to encourage and direct their efforts. Learning that two men were wounded and unable to pull back to the perimeter, 1LT Sisler charged from his position through intense weapons fire to assist them. He reached the men and began carrying one of them back to the perimeter, when he was overtaken by more intense fire by the enemy. Laying down his wounded comrade, he shot and killed three onrushing enemy soldiers, and silenced the enemy machine gun with a grenade. As he returned the wounded man to the perimeter, the left flank of the position came under extremely heavy attack by the superior enemy force, and several additional men of his platoon were quickly wounded. Realizing the need for instant action to prevent his position from being overrun, 1LT Sisler picked up some grenades and charged single-handedly into the enemy onslaught, firing his weapon and throwing grenades. Although his charge resulted in his untimely death, this singular, heroic action broke up the vicious assault and forced the enemy to begin withdrawing. His extraordinary leadership, infinite courage, and selfless concern for his men saved the lives of a number of his comrades.

1LT Sisler earned the Medal of Honor, Bronze Star and Purple Heart, all awarded posthumously. He was inducted into the MI Corps Hall of Fame in 1988, and the Intelligence Center dedicated Sisler Hall on Fort Huachuca in his honor the same year. On February 28, 1998, the US Navy commissioned the USNS Sisler, a Large Medium-Speed Rollon-Rolloff vessel in San Diego, California. The nomination packet, submitted by the Intelligence and Security Command, read "the naming of a LMSR after Lieutenant Sisler is a fitting tribute to all military and civilian personnel who have played an important role in the history of military intelligence and have paid the supreme sacrifice in their service to the nation."