Gulf of Tonkin Resolution

7 August 1964

The House unanimously approved the joint resolution — the Congressional Record later gave the tally as 416-0 — and the Senate approved it 88-2 on 7 August 1964.

Senators Wayne Morse of Oregon and Ernest Gruening of Alaska cast the only opposing votes. Morse characterized the measure as a predated declaration of war.

Congressional passage did not make it law: Johnson signed it as Public Law 88-408 on 10 August.

What the text authorized

The resolution endorsed the president's authority to take "all necessary measures" to repel attacks on U.S. forces and prevent further aggression.

It also declared the United States prepared, as the president determined, to use armed force to assist a SEATO member or protocol state requesting help in defense of its freedom — not any Southeast Asian country that asked. Congress issued no declaration of war.

The attack that was not there

Johnson had asked for the authority after the destroyers Maddox and Turner Joy reported a second North Vietnamese attack on 4 August. The administration presented that attack as established even though the ships' own reports already contained serious doubts, and the commander aboard Maddox had warned that freak weather and overeager sonar operators might explain many of them.

A declassified NSA historical study concluded that no 4 August attack occurred and that the supporting signals intelligence had been selectively and misleadingly presented. Johnson's retaliatory airstrikes had already been flown on 5 August, two days before the vote.