I found myself in the presence of men I had come to regard as my personal enemies. Some of them I recognized from the hard Geneva negotiations on Indochina four decades earlier. Others I knew by reputation for their roles in North Vietnam during our tragic war. Now, for the first time, some of us who helped make policy in Washington were meeting in Hanoi to discuss the war and the failed diplomatic efforts to end it earlier. We Americans hoped to engage the Vietnamese in an open discussion of missed opportunities and mistakes in perception that may have prolonged the conflict. Some of us may even have wanted a sort of absolution for our errors. We got neither. There were 13 Americans at the table in Hanoi, including six "witnesses" who had a part in U.S. policy (former defense secretary Robert McNamara, former undersecretary of state Nicholas Katzenbach, Gens. Dale Vesser and William Smith, former National Security Council staffer Francis Bator and I, a former NSC staffer and State Department adviser) and seven historians, some of whom have devoted virtually their whole careers to trying to construct a complete and accurate account of the American experience in Vietnam. The Vietnamese participants also included six former and present officials, as well as seven scholars, most of whom had had important military and civilian assignments during the war with the French and the war with the Americans. We had separate meetings with Foreign Minister Nguyen Manh Cam, a member of the Politburo, and Gen. Vo Nguyen Giap, the legendary military commander. Our conference -- the first of its kind -- lasted from June 18 to June 24.

A common factor in bringing all the Americans to Hanoi was curiosity. For the historians, especially, there was a desire to fill in the gaps, to test hypotheses, to confirm theories. For us witnesses, curiosity was directed more toward the people we had known of, but had not known, and toward particular events in which one or another of us was personally involved.

For myself, and I think for Bob McNamara and the others, contrition also played a part in the soul-searching as to whether or not to make the journey. I had thought that, by now, I had shed the trauma and guilt of the Vietnam War years, but the invitation from McNamara and professor James Blight of Brown University brought back sour memories of sleepless nights and frenetic days. Moreover, the prospect of spending almost a week in the close company of men with whom I exchanged glares and glowers across the conference hall in Geneva's Palais des Nations in 1954 and for much of 1961 and 1962 was not appealing. (In 1954, I was in the U.S. delegation at the Geneva Conference on Indochina, and in 1961 and 1962, I attended the Geneva Conference on Laos in the same capacity. I was with the CIA at the time.)

The organizers of the Hanoi conference had set aside one day to discuss several of the more consequential negotiating initiatives advanced by the Americans during the war. This was of particular interest to me. First, as a member of the NSC staff and later at the State Department under Ambassador-at-large Averell Harriman, I had spent several years desperately and fruitlessly seeking a formula that would bring the men of Hanoi to the negotiating table.

I have long been haunted by the ghosts of American overtures designed to bring an end to the war. Some of these apparently were dead on arrival when they reached Hanoi. Some suffered premature deaths at our own hand. President Lyndon Johnson and some of his closest advisers were under the illusion that the various emissaries we had recruited could deliver acceptable American negotiation proposals to Hanoi while, at the same moment, American B-52s were delivering bombs.

I was unable to determine in Hanoi last week how our peace probes during the '60s were actually dealt with by North Vietnamese leaders. Were they discussed and debated, or were they shrugged off as Washington's attempts to influence American public opinion? "In Washington," I said, "we would have brought in people from the CIA, the Pentagon, the State Department, anyone who had any expertise on the subject. We would examine each proposal carefully. Was it genuine? Was it a trap? There would be differences of opinion, arguments. But we'd reach a decision and send back a message to you." Several of the Vietnamese seemed uneasy. They probably anticipated what was coming next. "What happened when you first heard of our Phase A (We'll stop the bombing), Phase B (After about 10 days, you'll stop sending men and supplies into South Vietnam) proposal?" No reply. Finally, one former official murmured, "We are not permitted to say." (Some of what I do know about their decision-making I learned from documents just recently made available: Beijing exerted considerable pressure on Hanoi to continue to fight rather than to talk. Apparently, China was anxious to keep American troops engaged in Vietnam rather than have them free for use elsewhere.)

The Vietnamese participants reiterated ad nauseum during our meetings that they were not prepared to negotiate while bombs were falling on North Vietnam. Fair enough. But there were several bombing pauses during the late '60s, one lasting 40 days. On no occasion during these pauses did we receive anything like a robust hint or serious inquiry that would have indicated Hanoi was ready to negotiate an end to the war on any terms then remotely acceptable to Washington.

"You know," I reminded them, "there were many instances in 1966 and 1967 when we sent a message through one of our intermediaries that went far toward meeting your terms. Why didn't you at least agree to engage in secret talks about talking?"

"Why," replied one of their former Foreign Ministry officials, "did you always rely on third parties? Were you just making propaganda? Why didn't you try to contact us directly?" Why, indeed? Although we did try to meet with a North Vietnamese representative in Moscow and Rangoon and made a similar effort in Paris, it may be fair to say we could have tried harder, been more persistent.

After more than a day of discussion in Hanoi, however, I became convinced that our quest for a negotiated settlement between 1965 and 1968 had been a waste of time and effort. I said so. "I spent three years running around the world chasing after every hint, looking into every possibility that you were interested in a negotiated settlement. I have learned you were not and that I had been trying in vain. You say your motto was, Fight, fight -- Talk, talk,' but I didn't sense any willingness to talk." I am sure now that Hanoi had decided early on that, regardless of the sacrifices involved, they would continue to fight until they could confront the Americans with the kind of dramatic, demoralizing defeat they had inflicted on the French in the spring of 1954 at the battle of Dien Bien Phu, which broke France's will to continue their war in Indochina.

Naturally, we wanted to learn more about the Tet Offensive. In January-February 1968, during Tet, the Vietnamese New Year, a period usually marked by an informal cease-fire, Communist forces launched a massive surprise attack against major cities in South Vietnam. Downtown Saigon and the U.S. embassy itself suffered considerable damage. American and South Vietnamese casualties were high, but those of the Communist forces (especially the Viet Cong) were enormous. After several days of fierce fighting, the North Vietnamese and Viet Cong melted away into the countryside.

Tet has long been a subject of study by American analysts. The major burden of the attack was borne by young, inadequately trained Viet Cong troops. And it was they who suffered enormous casualties. Did South Vietnamese Communist leaders play a significant role in planning the attack? Were there recriminations when the Viet Cong casualties became known (if in fact they were revealed)? How did Hanoi react to these casualties and how was their military strength maintained despite the losses? McNamara raised some of these questions in the general sessions, but got little satisfaction. I gather that Gens. Vesser and Smith had better luck at lunch with the Vietnamese military. Gen. Giap acknowledged the high casualties but said the young had died for a good cause: independence and freedom.

Both Gen. Giap and Gen. William Westmoreland, the American commander, have claimed a military victory in the Tet Offensive, but the question of who won and who lost the military battle soon became irrelevant. The extent and intensity of the Communist attack, on the heels of optimistic American pronouncements on the course of the war, resulted in a major policy shift in Washington, followed by President Johnson's announcement that he would not seek reelection. Hanoi had its American Dien Bien Phu and felt it could negotiate from strength.

We Americans should have known what to expect during our sessions at the conference table last week. After all, the six American "witnesses" could hardly claim innocence or ignorance in connection with the millions of Vietnamese casualties, the terrible destruction wreaked on Vietnamese cities and countryside, the tearing asunder of Vietnam's social fabric. If we needed a reminder, it was close at hand last week. There was an almost total absence of middle-aged men on the streets of Hanoi, men who would have been of fighting age during the war. We were the object of several lectures on our perfidy.

As former officials of the American colossus, we should have expected the many references to how they, an economically backward, militarily inferior society, won the war against the American superpower.

And since our meeting took place in, and was co-sponsored by, a People's Republic -- one of few still extant -- we would have been misguided to expect an uninhibited and frank exchange of views.

It was evident from the outset that all of the formal Vietnamese presentations must have been cleared, perhaps even composed, well in advance by the leadership. Even their informal interventions, responses and reactions to American questions or assertions reflected concern and caution lest they digress from the line. In short, each speaker rang all the changes, touched all the bases, punched all the tickets. None of their presentations gave evidence that remarks by the Americans were even taken into account. We should not have been surprised by the Vietnamese claims that they had experienced no misperceptions and no wrong mind-sets about the United States, whereas we had been afflicted by gross misperceptions and mischievous mind-sets about Vietnam. Nor should we have been startled to hear that no opportunities to stop or shorten the war were missed by Hanoi, but that many were missed by the United States.

McNamara probed, pushed and prodded in an effort to get our Vietnamese hosts to agree that both sides had some responsibility for misperceptions and lost opportunities. He admitted, for example, that we gave short shrift to Vietnam's strong nationalist tradition and aspirations and that we were held in thrall by the Domino Theory and our conviction that Vietnam was a potential steppingstone for China's thrust into Southeast Asia. On the other hand, he stressed, the Vietnamese should understand that we had no desire or intention to replace France as a colonial power. "We were not opposed to a unified, independent Vietnam so long as it was not serving as a base for Soviet or Chinese expansion," he said. Although McNamara must have made this argument several times during the conference and at a separate meeting with Foreign Minister Cam, it seemed to make no impression on our hosts. Yes, we were wrong about them; no, they were not wrong about us.

The meetings were intense, long and trying. Even if each side had not been laden with heavy emotional baggage, communication would have been difficult. A few Americans could speak and understand Vietnamese and several Vietnamese could handle English. But I had a sense that important nuances were lost in translation from Vietnamese into English. Still, the simultaneous translations at our formal sessions were easier to bear than the consecutive translations at our meetings with Gen. Giap and Foreign Minister Cam. It was hard enough to look attentive and intelligent during the long monologues in Vietnamese. But it was even more difficult to appear patient and understanding when it turned out during the translation that they had been delivering anti-American diatribes very much along the lines we had been exposed to several times already.

The problem of translations and attention spans aside, the meetings could not have taken place in a more pleasant and convenient place. Hanoi's Hotel Metropole deserves its five stars. Its conference facilities are splendid. Perhaps most important, the efficient helpful, friendly English-speaking staff eased even the most onerous of our 10-hour days.

Someone must have been suffering a serious case of nerves about our conference despite the fact that it had been discussed in Hanoi by the American organizers on several occasions since November 1995. It had been agreed many months ago that CNN would film the proceedings for use sometime in the late summer or early autumn as the basis for an educational documentary film. But when we arrived at our hotel from the airport, we were told that the CNN arrangement had been canceled. (In the event, a compromise was reached; CNN could film one day's proceedings.)

Another hint that the meetings were a source of official unease was the fact that the press in Hanoi did not acknowledge the presence of us Americans or that a conference of such an historic nature was being held. Even our meeting with Gen. Giap was ignored.

When all was said and some of it was heard, we actually learned some things we had not known. The Vietnamese assured us, for example, that on two critical occasions -- the attack on American soldiers at Pleiku in February 1965 (which triggered the bombing of North Vietnam) and the attack on the U.S. destroyer Maddox in the Gulf of Tonkin in August 1964 (which, in effect, resulted in a congressional declaration of war) -- local commanders, not the High Command in Hanoi, were responsible. If so, the historians have some reworking to do.

I suppose in the cold reality of the morning after, it would be fair to say that the conference was less than a success. One could easily summon up a sense of deja vu; the sermons and the polemics did indeed remind me of some agonizing days at Geneva. But we had a price to pay in Hanoi. I think we paid it and I think our Vietnamese counterparts would agree that we paid it. At our next meeting, we can move from the past into the present. We will discuss the events of the '60s from a mutually held desire to achieve understanding, rather than score debating points. Chester Cooper served in the CIA, the White House and the State Department and is author of the "The Lost Crusade: America in Vietnam," published in 1970. He is now deputy director of Battelle Pacific Northwest National Laboratory. ** TRUCULENT, BITTER AND RIGID' In his 1970 book, "The Lost Crusade: America in Vietnam," Chester L. Cooper recalled his time as a member of the U.S. delegation at the Geneva Conference on Laos in 1961-62. Some of the North Vietnamese in Geneva were across the table from him during meetings in Hanoi last week. Here is a description from his book:

The North Vietnamese delegation was tough, truculent, bitter and rigid. Perhaps the men from Hanoi were in a bad temper because they were forced to spend their days denying what everyone knew was true -- the presence of North Vietnamese forces in Laos. Even the Russians admitted, albeit privately, that a substantial number of North Vietnamese troops were engaged in combat in Laos (the Americans and Laotians estimated that there were about 5,000), but the North Vietnamese rather stupidly insisted that they had not a single soldier there. (My head still resounds with the ringing cries of "The whole world knows that the United States calls white, black and black, white!" "On the contrary, we and the world know that black is black and white is white and that there are thousands of North Vietnamese fighting in Laos at this very moment!") As the months went by there was more and more evidence that North Vietnamese troops were not only in combat against the Royal Laotian Army, but were improving the network of trails going through Laos into South Vietnam. Already political cadres and military specialists and technicians were moving into South Vietnam to buttress the Viet Cong. CAPTION: Former U.S. defense secretary Robert McNamara, left, meets a wartime adversary, retired Vietnamese military commander Gen. Vo Nguyen Giap, recently in Hanoi at the end of the symposium on the Vietnam War.