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Tonkin Gulf Resolution

In August 1964 Congress passed the Tonkin Gulf Resolution (78 Stat. 384), approving and supporting President Lyndon B. Johnson's determination to repel any armed attack against U.S. forces in Southeast Asia. Johnson subsequently relied on the measure as his chief authorization for the escalation of the VIETNAM WAR.

The resolution was prompted by Johnson's report to Congress that the North Vietnamese had fired upon two U.S. destroyers in international waters in the Gulf of Tonkin, off the coast of North Vietnam. Johnson requested that Congress grant him wide PRESIDENTIAL POWERS to respond to the attacks of the North Vietnamese. Both houses of Congress voted overwhelmingly in favor of the resolution; only two senators opposed it and no representatives. The resolution gave the president power to "take all necessary measures to repel any armed attack against the forces of the United States and to prevent further aggression." According to the resolution, its purpose was to promote international peace and security and support the defense of U.S. naval vessels lawfully present in international waters from deliberate and repeated attacks by naval units of the Communist regime in Vietnam.

It was later revealed that the federal government had drafted the Tonkin Gulf Resolution fully six months before the attacks on the U.S. vessels occurred. It was also revealed that the United States provoked the attack by assisting the South Vietnamese in mounting clandestine military attacks against the North Vietnamese. Although the two U.S. vessels attacked were actually on intelligence-gathering missions, the North Vietnamese could not distinguish them from the South Vietnamese raiding ships. Johnson had also exaggerated the gravity of the attack itself, which did not harm either of the ships.

Although no formal declaration of war was ever issued for the Vietnam War, the JUSTICE DEPARTMENT and the STATE DEPARTMENT relied on the Tonkin Gulf Resolution as the functional equivalent. Thus, Johnson was able to send U.S. troops to Vietnam without an official war declaration. In early 1965 the Viet Cong raided a U.S. air base in South Vietnam, killing seven Americans. In response to that action, and in accordance with the Tonkin Gulf Resolution, Johnson began a large-scale escalation of U.S. involvement in the Vietnam War. The number of U.S. soldiers in South Vietnam grew from 25,000 in early 1965 to 184,000 by the end of that year. The escalation continued, and by 1968 543,000 U.S. soldiers were in South Vietnam.

Although the war initially had widespread support, by 1968 growing numbers of Americans had begun to protest and question John-son's decisions to escalate U.S. involvement. For a number of reasons, the public felt the president had deceived them. In the 1964 presidential elections, Johnson had campaigned on a promise to keep U.S. troops out of the fighting in Vietnam. In addition, the public learned through the release of the Pentagon Papers that the Tonkin Gulf incident was actually instigated by the United States and was not as damaging as the government had suggested. Some CONSTITUTIONAL LAW authorities argued that it was irrelevant whether Congress was deceived by the executive in passing the Tonkin Gulf Resolution because the resolution provided that Congress could repeal it at any time. In addition, the scholars argued that Congress had the power to stop appropriating money to support the war effort.

In January 1971 Congress repealed the Tonkin Gulf Resolution. President RICHARD M. NIXON continued the war effort, however, by relying on the commander in chief provisions of the U.S. Constitution. Congress continued to appropriate money to support the war effort. The Vietnam War was the longest, costliest, and most controversial war in U.S. history, and the Tonkin Gulf Resolution was the focal point of much of the controversy.


Moise, Edwin E. 1996. Tonkin Gulf and the Escalation of the Vietnam War. Chapel Hill: Univ. of North Carolina Press.

Siff, Ezra Y. 1999. Why the Senate Slept: The Gulf of Tonkin Resolution and the Beginning of America's Vietnam War. Westport, Conn.: Praeger.

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