August 4
Second Gulf of Tonkin Incident Reported
U.S. Navy reports of a second attack by North Vietnamese torpedo boats on destroyers in the Gulf of Tonkin prompted President Lyndon B. Johnson to order airstrikes and seek congressional authorization for expanded military action in Vietnam.
Summary
In the Gulf of Tonkin off North Vietnam, U.S. destroyers Maddox and Turner Joy conducted patrols amid rising tensions. After an August 2 clash, the ships reported another attack by North Vietnamese torpedo boats on the stormy night of August 4. Captain John Herrick later expressed doubts about the contacts, attributing some radar readings to weather or equipment issues. President Lyndon Johnson ordered retaliatory airstrikes and sought congressional authorization. The reported incident prompted the Gulf of Tonkin Resolution days later.
Context
The 1954 Geneva Accords had divided Vietnam at the 17th parallel after the First Indochina War, with the Democratic Republic of Vietnam in the north and the State of Vietnam in the south. Scheduled nationwide elections never occurred, and by the late 1950s South Vietnamese President Ngo Dinh Diem faced growing insurgency from communist-led forces backed by Hanoi. The United States, committed to containing communism under the domino theory, increased military advisers and support to Saigon while viewing North Vietnamese actions as part of broader Soviet and Chinese influence in Southeast Asia.
What Happened
On July 31, 1964, the destroyer USS Maddox began a signals-intelligence patrol (DESOTO mission) in the Gulf of Tonkin, staying outside claimed North Vietnamese territorial waters. South Vietnamese commandos had recently raided islands including Hon Me, heightening tensions. On August 2, three North Vietnamese P-4 torpedo boats from Squadron 135 approached and engaged the Maddox; the destroyer fired warning shots, and U.S. aircraft from the carrier USS Ticonderoga joined the fight, damaging the boats with four North Vietnamese sailors killed.
Aftermath
On the stormy evening of August 4, the Maddox—now joined by the destroyer USS Turner Joy—reported radar and sonar contacts interpreted as a second torpedo-boat attack. Captain John Herrick, the task-force commander, soon relayed doubts, citing possible weather effects, equipment issues, and misread communications intercepts. The Johnson administration nevertheless treated the reports as confirmation of aggression and ordered retaliatory airstrikes on August 5 against North Vietnamese naval facilities.
Legacy
The reported incidents directly produced the Gulf of Tonkin Resolution, passed by Congress on August 7 with near-unanimous support, which granted the president broad authority to assist any Southeast Asian nation threatened by communist aggression. This measure served as the legal foundation for the rapid escalation of U.S. combat forces in Vietnam without a formal declaration of war. Subsequent declassified National Security Agency studies and admissions by former officials, including Robert McNamara, established that no second attack occurred, shaping later debates over intelligence handling, executive war powers, and the origins of the Vietnam War.
Why It Matters
The resolution granted Johnson broad powers to escalate U.S. involvement in Vietnam without a formal declaration of war. It enabled the rapid buildup of American forces and shaped the course of the Vietnam War for years.
Related Questions
What was the Gulf of Tonkin Resolution?
It was a joint resolution of Congress that authorized President Johnson to take all necessary measures to repel armed attacks against U.S. forces and to prevent further aggression in Southeast Asia.
Did the second attack on August 4 actually occur?
Later U.S. government studies and admissions by officials concluded that no North Vietnamese vessels were present and the reported attack resulted from misidentified radar returns and faulty intelligence.
How did the incidents affect U.S. involvement in Vietnam?
The resolution provided the legal basis for the large-scale deployment of U.S. combat troops and the sustained bombing campaign against North Vietnam that followed.
What role did covert operations play in the lead-up to the incidents?
U.S.-backed South Vietnamese raids under OPLAN 34A and intelligence-gathering DESOTO patrols had increased tensions along the North Vietnamese coast in the weeks before the clashes.
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US Military Atlas: Second Gulf of Tonkin Incident Reported connects to military history, war consequences, or postwar diplomacy.
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Sources
- Gulf of Tonkin incident, Wikipedia. Accessed 2026-07-02.
- Gulf of Tonkin incident (1964), Britannica. Accessed 2026-07-02.