While patrolling international waters in the Gulf of Tonkin, the destroyer USS Maddox reported an attack by three North Vietnamese torpedo boats. The skirmish, and a disputed second attack days later, gave President Lyndon Johnson the pretext to seek the Gulf of Tonkin Resolution from Congress, which effectively authorized unlimited military escalation in Vietnam without a formal declaration of war.
The Maddox was on a signals-intelligence mission, code-named DESOTO, when North Vietnamese patrol boats approached. The destroyer opened fire first, then radioed for air support from the carrier USS Ticonderoga. In the ensuing exchange, one American aircraft was damaged, four North Vietnamese sailors killed, and not a single American life was lost.
What happened next mattered more than what happened that day. Within a week, Congress passed the Gulf of Tonkin Resolution by a vote of 416-0 in the House and 88-2 in the Senate, granting Johnson sweeping authority to wage war in Southeast Asia. A second reported attack on August 4, later shown to be almost certainly a false radar reading amid stormy seas and jittery sonar operators, provided the final justification.
Declassified documents and the Pentagon Papers later revealed that the administration exaggerated and possibly misrepresented the incidents to secure the resolution. Robert McNamara, defense secretary at the time, spent decades afterward defending and revising his account of what really happened in those dark waters.