The 20th anniversary of the Gulf of Tonkin Resolution this week is an occasion for a reassessment. For years it has been debated whether or not the Johnson administration deliberately misled Congress and the public about a second attack on United States destroyers in the gulf. But the information now available suggests that it was a classic case of self-deception and blundering deeper into conflict.
The accumulated evidence makes it reasonably certain that the alleged North Vietnamese PT boat attack of Aug. 4 was a figment of the US government's imagination. CIA Deputy Director Ray Cline evaluated the reports and intelligence data on the incident some days later and found the case for an attack uncon-vincing. But leading national-security officials were so geared up for a military confrontation with Hanoi that they refused to consider evidence that it was not happening. They believed that Hanoi had attacked the Maddox on Aug. 2 because it saw a connection between the US ship and South Vietnamese commando raids on North Vietnamese islands on July 31. They expected the same thing to happen after another commando raid on the coast Aug. 3-4. And they knew that this time, the President wanted to retaliate against the North.
Word reached the Pentagon on the morning of Aug. 4 that an intercepted North Vietnamese message indicated a ''naval action'' was imminent. Although the message did not say that it would take the form of an attack, it triggered a process of preparing for retaliatory action that had an irreversible momentum. Before the first reports from the Maddox that an attack was under way, Defense Secretary Robert S. McNamara and other Pentagon officials immediately met to discuss various options for retaliatory strikes against North Vietnam.
Even after the commander of the two destroyers warned that earlier reports of torpedo attacks were in doubt and recommended that no further action be taken until after a ''complete evaluation,'' the preparations for air attacks continued. Mr. McNamara spent a little more than one hour with the Joint Chiefs of Staff considering whether an attack had taken place before releasing the strike order - without benefit of any complete evaluation of the incident. It took President Lyndon Johnson only 18 minutes of discussion with his advisers to approve the strike. When the planes took off to bomb North Vietnamese targets that night, detailed reports from the two destroyers had not even reached Washington.
More serious than this rampant subjectivity and excessive haste in considering the evidence and using force was the administration's ignorance of the effect its bombings would have on Hanoi's policy. US officials believed that graduated military pressure on the North, combined with other evidence of US determination to escalate and direct threats to devastate the North, would force Hanoi to reconsider its support for the war in the South. The first such direct threat had been conveyed to Hanoi in June via a Canadian diplomat, and the threat was repeated through the same channel a few days after the Tonkin bombings.
This campaign to coerce Hanoi was based on an image of the North Vietnamese as foreign aggressors in the South whose ''ambitions'' could be curbed by raising the cost high enough. A serious effort to understand Hanoi's perspective on the war and on the issue of North-South relations, however, would have suggested the probability that a demonstration by the US of an intention to carry the war to the North would push Hanoi's leaders into direct participation in combat in the South rather than forcing them to step back from the war. According to three Vietnamese officials I interviewed recently, a few days after the Tonkin Gulf reprisals the Vietnamese Communist leadership secretly convened a Central Committee plenum to consider the implications of the American move. Party leaders concluded that direct US military intervention in the South and the bombing of the North were probable, and that the party and government had to prepare for a major war in the South. In September the first combat units of the Vietnam People's Army began to move down the Ho Chi Minh Trail.
The self-defeating errors of the Tonkin crisis were not unique to that administration or that conflict. The subjective expectation of aggressive action by an adversary can create imaginary threats and lead to unnecessary violence. Ignorance of an adversary's viewpoint may cause a state to provoke unwittingly an action it would have wished to avoid. Until US decisionmakers are trained to think about managing conflict in a more disciplined way, the risk of blundering into confrontation will never be far off.