Nam Dong sat in a valley 32 miles west of Da Nang, near the Laotian border, a position that made it a persistent irritant to Viet Cong operations in the region. The camp's one saving grace was its construction: the Americans had built it around the bones of an old French fort. The twelve U.S. Special Forces soldiers and their Australian adviser lived inside the fort's inner walls, while the 311 Montagnard Strikers, 50 Nung bodyguards, and seven South Vietnamese soldiers occupied the outer perimeter. The arrangement was meant to create layered defenses. In practice, it also kept the feuding factions physically separated. Intelligence was almost nonexistent. The camp had no spy network in the surrounding villages, and when the Viet Cong executed two local chiefs on 5 July, the resulting agitation among the populace yielded no actionable information. Captain Donlon, sensing danger, doubled the guard and stockpiled ammunition at fighting positions. His South Vietnamese counterpart, Captain Lich, sent out no patrols.

The attack came in the early hours of 6 July. Viet Cong and PAVN forces struck the outer perimeter with concentrated fire, attempting to overwhelm the camp before its defenders could organize. What followed was a chaotic, close-quarters fight in the dark. Donlon, wounded multiple times during the battle, moved from position to position, redistributing ammunition, directing fire, and at one point carrying a critically wounded teammate to cover. The inner fort held, but the cost was severe. Warrant Officer Kevin Conway of the Australian Army Training Team Vietnam died in the assault, becoming the first Australian killed in action in the Vietnam War. Master Sergeant Gabriel Alamo and Sergeant John Houston were also killed. Both Americans received posthumous Distinguished Service Crosses. Sergeant Terrance Terrin, the team's medic, earned a Silver Star for treating the wounded under fire throughout the night. At least 62 attackers and 57 South Vietnamese defenders died before the fighting ended.

As dawn broke over the valley, a U.S. Army CV-2 Caribou transport aircraft managed to drop ammunition into the battered camp. Republic of Vietnam Air Force A-1 Skyraiders followed, strafing the Viet Cong positions ringing the perimeter. The attackers, unable to finish what they had started in the darkness, withdrew. The camp that nobody had thought worth defending had survived, though barely. For his actions that night, Roger Donlon became the first recipient of the Medal of Honor in the Vietnam War, awarded by President Lyndon Johnson in December 1964. The battle resonated far beyond the valley. It demonstrated the vulnerability of isolated Special Forces camps, the critical role of indigenous forces in the war's early years, and the kind of close combat that would define the conflict for the next decade.

The battle at Nam Dong entered American popular culture four years later when a scene in the 1968 John Wayne film The Green Berets was directly inspired by the engagement. The film, one of the few major Hollywood productions made during the war itself, dramatized the kind of isolated outpost defense that Nam Dong exemplified. But the real legacy of the battle lies in what it revealed about the war's trajectory in 1964. The United States had fewer than 25,000 military advisers in Vietnam that July. Within a year, that number would multiply tenfold. The Viet Cong's ability to mass forces and nearly overrun a fortified position this early in the conflict signaled to American military planners that the advisory mission was not enough. Nam Dong's valley is quiet now, the old camp long reclaimed by the jungle, but the battle fought there helped set in motion the escalation that would consume both nations for another decade.