Robert O'Malley was one of four brothers, all of them two years apart in age and two years apart in joining the Marine Corps. Like his brothers, he enlisted after graduating from high school. He was stationed for a time in Okinawa, and in May 1965 went to Vietnam with the 3rd Marine Division.
Late in the summer, U.S. intelligence learned that the Vietcong was planning an attack on the American base at Chu Lai. The Marines designed Operation Starlight, an offensive in which three Marine battalions would block the assault. It was the first major engagement between the Americans and the Vietcong, and the Marines weren't yet familiar with the enemy's guerrilla tactics.
At dawn on August 18, Corporal O'Malley's 3rd Battalion made an amphibious landing near the village of An Cu'ong 2. Almost immediately, more than 1,200 Vietcong hidden in the ridges began to mortar the Marines, knocking out three tanks that were part of the operation. When O'Malley saw that the enemy was firing from a trench line beyond an open rice paddy, he charged toward it. Leaping into the trench line, he killed eight soldiers with his rifle and hand grenades, then ran back to his squad. After aiding in the evacuation of several wounded Marines, he returned to the area of heaviest fighting and helped repel another assault.
O'Malley was finally ordered to evacuate his battered squad. As he led the way to a helicopter landing zone, he was hit by mortar shrapnel in his legs, arm, and lung and began coughing up blood. Despite his wounds, he moved to an exposed position so he could lay down suppressive fire as his men boarded a chopper. Only after they were all safely aboard did he allow himself to be removed from the battlefield.
It took more than four months for the shrapnel in his lungs to stop shifting so that O'Malley could be operated on. After undergoing surgery in Japan, he was sent back to Camp Pendleton and finished out his tour there, leaving the service in April 1966. Late that fall, he was informed that he was to receive the Medal of Honor. He was flown on Air Force One to Austin, Texas, where President Lyndon Johnson was meeting with the Joint Chiefs of Staff. The president presented the medal to O'Malley on December 6, 1966.