She was among the destroyers that protected aircraft from the carriers on Yankee Station in the Tonkin Gulf. During periods of sustained air operations against North Vietnam "Leary", along with the other destroyers on patrol, were responsible for providing protective cover for as many as three aircraft carriers at once. This included firing her guns and destroying missile placements in North Vietnam that were firing at the fleet. Her guns were often fired during naval gunfire support missions. "Leary" was also regularly called upon to provide emergency search and rescue duties, and was responsible for saving the lives of many who would otherwise have been lost at sea.