What really happened in the Gulf of Tonkin in 1964?

On Tuesday morning, Aug. 4, 1964, Defense Secretary Robert McNamara called President Lyndon Johnson with a report about a possible confrontation brewing in southeast Asia.

“Mr. President, we’ve just had a report from the commander of that task force out there … The report is that they have observed — and we don't know by what means — two unidentified vessels and three unidentified prop aircraft in the vicinity of the destroyers,” McNamara told the president.

Related: LBJ knew the Vietnam War was a disaster in the making. Here's why he couldn't walk away.

Forty-eight hours earlier, on Aug. 2, two US destroyers on patrol in the Gulf of Tonkin — the Maddox and the Turner Joy — were attacked by North Vietnamese boats. Unlike much else that followed, this incident is undisputed, although no one from the US government ever admitted publicly that the attack was likely provoked by its covert actions.

No one was hurt and little damage was done in the attack, but intercepted cables suggested a second attack might be imminent. McNamara was ready to respond.

“We have ample forces to respond not only to these attacks on these destroyers but also to retaliate, should you wish to do so, against targets on the land,” he told the president.

Unlike McNamara, Johnson, on the morning of Aug. 4, 1964, was in less of a hurry to respond to an attack. Any escalation in the bombing of the North risked provoking the Russians or, more likely, the Chinese. Both countries were backing North Vietnam, but so far they were staying out of the conflict and the White House wanted to keep it that way.

But only a few minutes later, McNamara was back on the line with news of a second incident in the Gulf of Tonkin.

Listen to McNamara's conversation with Johnson. 

Over the next 12 hours, as the president's team scrambled to understand what had happened and to organize a response, the facts remained elusive. Around midday on Aug. 4, Adm. Grant Sharp, the top navy commander in the Pacific, made a call to the Joint Chiefs, and it was clear there were significant doubts about this second incident. He read the chiefs a cable from the captain of the Maddox.

Listen to that cable. 

As it turns out, Adm. Sharp failed to read to the Joint Chiefs the last line of the cable, which read: “Suggest a complete evaluation before any further actions.”

Despite this tremendous uncertainty, by midafternoon, the discussion among Johnson and his advisers was no longer about whether to respond but how.

In a conversation with McNamara on Aug. 3, after the first incident, Johnson indicated he had already thought about the political ramifications of a military response and had consulted with several allies.

“The people who are calling me up, they want to be damned sure I don't pull 'em out and run, and they want to be damned sure that we're firm. That’s what all the country wants, because Goldwater's raising so much hell about how he's gonna blow 'em off the moon, and they say that we oughtn't to do anything that the national interest doesn't require. But we sure ought to always leave the impression that if you shoot at us, you're going to get hit,” Johnson said. 

It was 1964, an election year, and the Republicans had just nominated Barry Goldwater, a former jet fighter pilot, and hardcore hawk, to run against Johnson in November.

Through the evening of Aug. 4, while no new information arrived to clarify the event in the Gulf, the White House narrative was firmly in place. “We're going to retaliate and we’ll make an announcement a little later in the evening, in the next hour or so and we’ll ask Congress for a resolution of war the next day to support us,” Johnson told an old friend.

That night, on national television, Johnson addressed the American people, saying, “Renewed hostile actions against United States ships on the high seas in the Gulf of Tonkin have today required me to take action and reply. Our response, for the present, will be limited and fitting. We still seek no wider war.”

And so, in the course of a single day, and operating on imperfect information, Johnson changed the trajectory of the Vietnam War.

Two days later, the Gulf of Tonkin resolution sailed through both houses of Congress by a vote of 504 to 2.

“LBJ was looking for a pretext to go to Congress to ask for a resolution that would give him the authority to do basically whatever the hell he wanted to do in Vietnam, without the intense public debate that a declaration of war would have required,” says historian Chris Oppe.

“But, to me, the more pernicious deception was this idea that American ships were sailing innocently in the Gulf of Tonkin and were attacked without provocation,” he continues. “In fact, the United States had been waging a small, secret war against North Vietnam since 1961. In the days leading up to the first incident of August 2nd, those secret operations had intensified.”

In a conversation with Johnson, McNamara confirmed this, with a reference to OP-CON 34A, a covert operation against the North Vietnamese.

Listen to that exchange. 

So, whether by accident or design, American actions in the Tonkin Gulf triggered a response from the North Vietnamese, not the other way around.

Historians still disagree over whether Johnson deliberately misled Congress and the American people about the Tonkin Gulf incident or simply capitalized on an opportunity that came his way. But, interestingly, on Sept. 18, a similar incident occurred in the Gulf of Tonkin. This time, however, President Johnson reacted much more skeptically and ultimately decided to take no retaliatory action.

Two nearly identical episodes six weeks apart; two nearly opposite responses. Did Johnson learn something from the first experience?

“I would not suggest that he learned from the Gulf of Tonkin incident so much as that he got from it exactly what he wanted, which was an enormous bump in approval ratings — 30 percent overnight,” says historian Chris Oppe.

“One of the great ironies of the Gulf of Tonkin incident for President Johnson is that it was for him, politically, a great success,” he continues. “It set a very terrible precedent, which is that he would go on to escalate further, not with any striking confidence that his objectives will be achieved, but only with the assurance that, unless he embarked on these massive military escalations, America would fail in Vietnam and he might well be labeled the only president in American history to lose a war.”

This article is based on the PRI podcast, LBJ's War, hosted by David Brown. Subscribe to LBJ's War on Apple Podcasts.