At the time of the incident, Secretary of State Rusk was questioned on NBC television:

The Tonkin «attack» brought a congressional resolution, passed unanimously in the House, and with only two dissenting votes in the Senate, giving Johnson the power to take military action as he saw fit in Southeast Asia.

Two months before the Gulf of Tonkin incident, U.S. government leaders met in Honolulu and discussed such a resolution. Rusk said, in this meeting, according to the Pentagon Papers, that "public opinion on our Southeast Asia policy was badly divided in the United States at the moment and that, therefore, the President needed an affirmation of support."

The Tonkin Resolution gave the President the power to initiate hostilities without the declaration of war by Congress that the Constitution required. The Supreme Court, supposed to be the watchdog of the Constitution, was asked by a number of petitioners in the course of the Vietnam war to declare the war unconstitutional. Again and again, it refused even to consider the issue.

Immediately after the Tonkin affair, American warplanes began bombarding North Vietnam. During 1965, over 200,000 American soldiers were sent to South Vietnam, and in 1966, 200,000 more. By early 1968, there were more than 500,000 American troops there, and the U.S. Air Force was dropping bombs at a rate unequaled in history. Tiny glimmerings of the massive human suffering under this bombardment came to the outside world. On June 5, 1965, the New York Times carried a dispatch from Saigon:

As the Communists withdrew from Quangngai last Monday, United States jet bombers pounded the hills into which they were headed. Many Vietnamese-one estimate is as high as 500-were killed by the strikes. The American contention is that they were Vietcong soldiers. But three out of four patients seeking treatment in a Vietnamese hospital afterward for burns from napalm, or jellied gasoline, were village women.

On September 6, another press dispatch from Saigon:

In Bien Hoa province south of Saigon on August 15 United States aircraft accidentally bombed a Buddhist pagoda and a Catholic church… it was the third time their pagoda had been bombed in 1965. A temple of the Cao Dai religious sect in the same area had been bombed twice this year.

In another delta province there is a woman who has both arms burned off by napalm and her eyelids so badly burned that she cannot close them. When it is time for her to sleep her family puts a blanket over her head. The woman had two of her children killed in the air strike that maimed her.

Few Americans appreciate what their nation is doing to South Vietnam with airpower… innocent civilians are dying every day in South Vietnam.

Large areas of South Vietnam were declared "free fire zones," which meant that all persons remaining within them-civilians, old people, children-were considered an enemy, and bombs were dropped at will. Villages suspected of harboring Viet Cong were subject to "search and destroy" missions-men of military age in the villages were killed, the homes were burned, the women, children, and old people were sent off to refugee camps. Jonathan Schell, in his book The Village of Ben Suc, describes such an operation: a village surrounded, attacked, a man riding on a bicycle shot down, three people picnicking by the river shot to death, the houses destroyed, the women, children, old people herded together, taken away from their ancestral homes.

The CIA in Vietnam, in a program called "Operation Phoenix," secretly, without trial, executed at least twenty thousand civilians in South Vietnam who were suspected of being members of the Communist underground. A pro-administration analyst wrote in the journal Foreign Affairs in January 1975: "Although the Phoenix program did undoubtedly kill or incarcerate many innocent civilians, it did also eliminate many members of the Communist infrastructure."

After the war, the release of records of the International Red Cross showed that in South Vietnamese prison camps, where at the height of the war 65,000 to 70,000 people were held and often beaten and tortured, American advisers observed and sometimes participated. The Red Cross observers found continuing, systematic brutality at the two principal Vietnamese POW camps-at Phu Quoc and Qui Nhon, where American advisers were stationed.

By the end of the Vietnam war, 7 million tons of bombs had been dropped on Vietnam, more than twice the total bombs dropped on Europe and Asia in World War II-almost one 500-pound bomb for every human being in Vietnam. It was estimated that there were 20 million bomb craters in the country. In addition, poisonous sprays were dropped by planes to destroy trees and any kind of growth-an area the size of the state of Massachusetts was covered with such poison. Vietnamese mothers reported birth defects in their children. Yale biologists, using the same poison (2,4,5,T) on mice, reported defective mice born and said they had no reason to believe the effect on humans was different.

On March 16, 1968, a company of American soldiers went into the hamlet of My Lai 4, in Quang Ngai province. They rounded up the inhabitants, including old people and women with infants in their arms. These people were ordered into a ditch, where they were methodically shot to death by American soldiers. The testimony of James Dursi, a rifleman, at the later trial of Lieutenant William Calley, was reported in the New York Times:

Lieutenant Calley and a weeping rifleman named Paul D. Meadlo-the same soldier who had fed candy to the children before shooting them-pushed the prisoners into the ditch…

"There was an order to shoot by Lieutenant Calley, I can't remember the exact words-it was something like 'Start firing.

"Meadlo turned to me and said: 'Shoot, why don't you shoot?

"I was crying. "I said, 'I can't. I won't.

"Then Lieutenant Calley and Meadlo pointed their rifles into the ditch and fired.

"People were diving on top of each other; mothers were trying to protect their children…"

Journalist Seymour Hersh, in his book My Lai 4, writes:

When Army investigators reached the barren area in November, 1969, in connection with the My Lai probe in the United States, they found mass graves at three sites, as well as a ditch full of bodies. It was estimated that between 450 and 500 people — most of them women, children and old men-had been slain and buried there.

The army tried to cover up what happened. But a letter began circulating from a GI named Ron Ridenhour, who had heard about the massacre. There were photos taken of the killing by an army photographer, Ronald Haeberle. Seymour Hersh, then working for an antiwar news agency in Southeast Asia called Dispatch News Service, wrote about it. The story of the massacre had appeared in May 196B in two French publications, one called Sud Vietnam en Lutte, and another published by the North Vietnamese delegation to the peace talks in Paris-but the American press did not pay any attention.

Several of the officers in the My Lai massacre were put on trial, but only Lieutenant William Calley was found guilty. He was sentenced to life imprisonment, but his sentence was reduced twice; he served three years-Nixon ordered that he be under house arrest rather than a regular prison-and then was paroled. Thousands of Americans came to his defense. Part of it was in patriotic justification of his action as necessary against the "Communists." Part of it seems to have been a feeling that he was unjustly singled out in a war with many similar atrocities. Colonel Oran Henderson, who had been charged with covering up the My Lai killings, told reporters in early 1971: "Every unit of brigade size has its My Lai hidden someplace."

Indeed, My Lai was unique only in its details. Hersh reported a letter sent by a GI to his family, and published in a local newspaper: