He joined the Navy on January 8, 1962 to be a Navy Seabee. He was assigned to the Naval Air Station at Glynco, Georgia for apprenticeship training in May which he completed in May 1963. In September, he was assigned to take Construction Mechanic training at the Naval Construction Training Center at Port Hueneme, California which he completed that month. Afterwards, he was assigned to Alfa Company, Naval Mobile Construction Battalion 11. On November 18, he deployed to Okinawa and was assigned there until September 1964. On November 1, he was assigned to Seabee Team 1104, Naval Construction Battalion 11, and completed Seabee team training at Port Hueneme on January 22, 1965. The Seabee team consisted of nine Seabees including one officer. Shields and Seabee Team 1104 deployed to Saigon, Republic of Vietnam arriving on February 1, 1965. On March 28, Seabee Team 1104 was assigned to construct a U.S. Army Special Forces Camp at Ben Soi, completing their construction work on June 3. Seabee Team 1104 was next assigned to a newly established Army Special Forces Camp at Dong Xoai about 55 miles northwest of Saigon arriving on June 4, to assist in repair and construction of the compound which included an adjacent compound with the district headquarters building. An 11-man Army Special Forces team was in charge of the northern compound of Green Berets, Seabees, and 200 Montagnards. The adjacent compound was occupied by over 200 South Vietnamese Army soldiers.
On the night of June 9, 1965, the unfinished Army Special Forces Camp at Dong Xoai was mortared and attacked by the 272nd Vietcong Regiment, and the Special Forces compound was captured the next morning. After being wounded by mortar fire, Shields fought with Special Forces soldiers against the enemy carrying up needed ammunition to the firing line positions. Although wounded again by shrapnel and shot in the jaw on June 10, he helped a soldier and a Seabee carry the badly wounded Special Forces captain in charge of the camp to a safer position in the compound. After four more hours of fighting, and greatly weakened, Shields volunteered to help Special Forces Second Lieutenant Charles Q. Williams who now was the acting commander since the Special Forces commander was one of the first badly wounded in the battle, destroy a Vietcong machine gun outside the perimeter which was threatening to kill everyone now in the adjacent district headquarters building which was now under the lieutenant's command and its occupants holding off the Vietcong attackers from all sides. The lieutenant armed with a 3.5 rocket launcher which was loaded by Shields, destroyed the machine gun, and on the way back to the building Williams was wounded for the 4th time and Shields for the third time, shot in both legs. Shields was air-evacuated afterwards from Dong Xoai with five other Seabees by the direction of the lieutenant to Saigon on June 10 and died during the evacuation. Two Seabees of Team 1104, Shields and SW2 William C. Hoover lost their lives and seven of his Seabee team were wounded in the first two days of the Battle of Dong Xoai. Three Army Special Forces soldiers were also killed, plus several members of other American military units and many members of South Vietnamese military units which partook in the battle were killed and wounded.
Burial
Shields was buried with a Marine Corps honor guard at Gardiner Cemetery, Gardiner, Washington on June 19, 1965. His name is listed on the Vietnam Veterans Memorial on Panel 02E, Row 007.
Medal of Honor
Shields was posthumously presented the Medal of Honor at a ceremony at the White House on September 13, 1966. His wife received the award from President Lyndon B. Johnson in the presence of his father, mother, daughter, and brother. Special Forces Lieutenant Williams was also present during the ceremony and had himself received the Medal of Honor on July 5, 1966, for his heroic actions during the 14-hour siege of the Special Forces Camp at Dong Xoai. All twenty of the Seabees and Special Forces soldiers were personally awarded for their actions at Dong Xoai. Shields' other military decorations and awards include: the Purple Heart Medal with two Gold Stars, Navy Unit Commendation, Navy Good Conduct Medal, National Defense Service Medal, Vietnam Service Medal with two campaign stars, RVN Gallantry Cross with Palm, RVN Military Merit Medal, RVN Gallantry Cross Unit Citation with palm and frame, RVN Civil Actions Unit Citation with palm and frame, and RVN Campaign Medal with 1960- device,
