The Gulf of Tonkin: the second attack that never happened

A White House Situation Room memorandum to President Johnson reports that the destroyer USS Maddox was attacked by three North Vietnamese (DRV) PT boats in the Gulf of Tonkin. The Maddox returned fire with its 5-inch guns, and jets from the Ticonderoga made strafing attacks on the boats.

President Johnson publicly instructs the Navy to continue patrols off North Vietnam, add a second destroyer, provide combat air cover, and destroy any force that attacks in international waters. The order sets up the second patrol of August 4.

At 11:36 p.m. EDT, President Johnson tells the nation on radio and television that renewed hostile actions against U.S. ships in the Gulf of Tonkin have required a military response. He announces retaliatory air strikes and asks Congress for a resolution. The source is the record of the address; the attack it describes was later found not to have occurred.

Congress passes the joint resolution giving the President broad authority to use force in Southeast Asia. Only two Senators, Wayne Morse and Ernest Gruening, vote against it. The National Archives notes that the Maddox's captain had already cabled that weather effects on radar and overeager sonarmen may have accounted for many of the August 4 reports.

The joint resolution is approved as Public Law 88-408 (78 Stat. 384). Its preamble states that 'naval units of the Communist regime in Vietnam' have 'deliberately and repeatedly attacked United States naval vessels lawfully present in international waters.'

Secretary of Defense Robert S. McNamara testifies before the Senate Foreign Relations Committee on the August 1964 incidents in the Gulf of Tonkin. The hearing is published as 'The Gulf of Tonkin, the 1964 Incidents. Part 1'.

Section 12 of Public Law 91-672, an act amending the Foreign Military Sales Act, terminates the joint resolution of August 10, 1964 (78 Stat. 384; Public Law 88-408), effective when the second session of the 91st Congress adjourns. The act is approved January 12, 1971.

The National Security Agency declassifies more than 140 formerly top secret documents, including NSA historian Robert J. Hanyok's article, first published in the agency's classified Cryptologic Quarterly. Hanyok concludes that no second attack took place and that signals intelligence was handled so that it seemed to fit the claim of an attack. The release came a month after The New York Times reported on October 31, 2005 that the study was being kept secret.

Secrecy News reports that NSA has declassified and released, in response to a Mandatory Declassification Review request, about 95 percent of Robert J. Hanyok's 2002 history 'Spartans in Darkness: American SIGINT and the Indochina War, 1945-1975.' On the Gulf of Tonkin, the review of the signals intelligence shows that 'no attack happened that night' of August 4, 1964.