Milestone Documents

Tonkin Gulf Resolution (1964)

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Citation: Tonkin Gulf Resolution; Public Law 88-408, 88th Congress, August 7, 1964; General Records of the United States Government; Record Group 11; National Archives. Tonkin Gulf Resolution, Senate roll call tally sheet, 08/07/1964; SEN 88A-M1, Misc Roll Calls, 88th Congress, 2nd Session; Record Group 46, Records of the U. S. Senate; National Archives.

This joint resolution of Congress (H.J. RES 1145), dated August 7, 1964, gave President Lyndon Johnson authority to increase U.S. involvement in the war between North and South Vietnam.

On the evening of August 4, 1964, President Lyndon Johnson addressed the nation in a televised speech in which he announced that two days earlier, U.S. ships had been attacked twice in international waters in the Gulf of Tonkin near North Vietnam. Johnson dispatched U.S. planes against the attackers and asked Congress to pass a resolution to support his actions.

There was little debate in Congress, and the joint resolution "to promote the maintenance of international peace and security in southeast Asia" passed on August 7, with only two Senators (Wayne Morse and Ernest Gruening) dissenting.

The Tonkin Gulf Resolution became the subject of great political controversy in the course of the undeclared war that followed. It stated that "Congress approves and supports the determination of the President, as Commander in Chief, to take all necessary measures to repeal any armed attack against the forces of the United States and to prevent any further aggression." As a result, President Johnson, and later President Nixon, relied on the resolution as the legal basis for their military policies in Vietnam.

There were two incidents in the Gulf of Tonkin in the days preceding Johnson's speech. On August 2 – the first Tonkin Gulf incident – North Vietnamese torpedo boats were spotted and attacked the destroyer USS Maddox. The Maddox was conducting electronic eavesdropping on North Vietnam to assist South Vietnamese Army (ARVN) commando raids on North Vietnamese targets, but that wasn't publicly known at the time. Historians now suspect the North Vietnamese boats had set out to attack an ARVN raid in progress when it encountered the Maddox.

Then on August 4, the USS Maddox captain reported a second incident, that he was "under continuous torpedo attack." He later cabled "freak weather effects on radar and overeager sonarmen may have accounted for many reports," but Defense Secretary Robert McNamara did not report the captain's doubts to President Johnson. (A 2002 National Security Agency report made available in 2007 confirmed the August 2 attack, but concluded the August 4 attack never happened.)

Johnson portrayed confrontations between U.S. and North Vietnamese ships off the coast of North Vietnam as unprovoked aggression when he addressed Congress. When contrary information later surfaced, many believed Congress had been conned, but it was too late.

The Gulf of Tonkin act became more controversial as opposition to the war mounted. A Senate investigation revealed that the Maddox had been on an intelligence mission in Tonkin Gulf, contradicting Johnson’s denial of U.S. Navy support of such missions. The Resolution was repealed in January 1971 in an attempt to curtail President Nixon’s power to continue the war.


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Eighty-eighth Congress of the United States of America

Begun and held at the City of Washington on Tuesday, the seventh day of January, one thousand nine hundred and sixty-four

Joint Resolution
To promote the maintenance of international peace and security in southeast Asia.

Whereas naval units of the Communist regime in Vietnam, in violation of the principles of the Charter of the United Nations and of international law, have deliberately and repeatedly attacked United States naval vessels lawfully present in international waters, and have thereby created a serious threat to international peace; and

Whereas these attackers are part of deliberate and systematic campaign of aggression that the Communist regime in North Vietnam has been waging against its neighbors and the nations joined with them in the collective defense of their freedom; and

Whereas the United States is assisting the peoples of southeast Asia to protest their freedom and has no territorial, military or political ambitions in that area, but desires only that these people should be left in peace to work out their destinies in their own way: Now, therefore be it

Resolved by the Senate and House of Representatives of the United States of America in Congress assembled, That the Congress approves and supports the determination of the President, as Commander in Chief, to take all necessary measures to repel any armed attack against the forces of the United States and to prevent further aggression.

Section 2. The United States regards as vital to its national interest and to world peace the maintenance of international peace and security in southeast Asia. Consonant with the Constitution of the United States and the Charter of the United Nations and in accordance with its obligations under the Southeast Asia Collective Defense Treaty, the United States is, therefore, prepared, as the President determines, to take all necessary steps, including the use of armed force, to assist any member or protocol state of the Southeast Asia Collective Defense Treaty requesting assistance in defense of its freedom.

Section 3. This resolution shall expire when the President shall determine that the peace and security of the area is reasonably assured by international conditions created by action of the United Nations or otherwise, except that it may be terminated earlier by concurrent resolution of the Congress.