The Gulf of Tonkin incident , also known as the USS Maddox incident, was a disputed international confrontation that led to the United States engaging more directly in the Vietnam War. It involved both a real confrontation and a fabricated confrontation between ships of North Vietnam and the United States in the waters of the Gulf of Tonkin. The original American report blamed North Vietnam for both incidents, but the Pentagon Papers, the memoirs of Robert McNamara, and NSA publications from 2005, proved that the US government lied to justify a war against Vietnam.