he Vietnam War came out of the closet at a conference here last week. It revealed itself as something that almost anybody involved, however directly or remotely, can argue about in a reasonably civil and constructive way.

And I do mean almost anybody. The conference assembled by a nonprofit organization called the World Without War Council brought together a unique grab bag of former policymakers, war veterans and war protesters, journalists and academics--those who planned the war, fought it, wrote about it, opposed it in the streets.

The topic was "Vietnam and the Opinion Makers." The stated aim was to examine how all the forces at work on public opinion in the Vietnam years could "contribute most effectively to the best possible U.S. foreign policy during the rest of this century."

The idea was to skip well-worked-over wrangles having to do with sabotage by the press or dissembling by the government. But, of course, there was no way this crowd could forego some blunt and bitter recycling of old arguments over who lost the war. And there was no way, either, to expect the participants to wind up in one day with anything remotely resembling a consensus on how to do it better next time--if only because "next time" was impossible to define.

But something of real value did emerge. The inescapable conclusion I came away with is that just as the stereotypical "Vietnam veteran" (anti-war, anti-social, psychologically stressed) is a gross oversimplification, so the celebrated "Vietnam syndrome" is not what it's been cracked up to be.

It exists--but not as an absolute rejection of anything in American foreign policy that remotely embraces the impulses and purposes that gradually ensnared this country, increment by creeping increment, in the Vietnam tragedy. It is not blindly anti-defense, or anti- military intervention, or anti-deterrence of communism.

But neither does it take the form of dogged refusal to confront head-on the excesses, failures, misjudgments and misrepresentations that contributed to the failure of the Vietnam mission.

The real Vietnam syndrome is more complicated, more questioning--and a lot more constructive--than that. And for just that reason, its impact on public attitudes toward this country's future role in the world is likely to be all the more profound.

Or so it struck me, watching Vietnam combat veterans listen carefully to William P. Bundy, a major participant as assistant secretary of state in Vietnam policymaking. Bundy was presenting the Johnson administration's version of the Tonkin Gulf incident, a critical turning point in American involvement in the war.

Gloria Emerson, one of the best of the war correspondents, called Barry Zorthian, once the official spokesman for the press at Mission headquarters in Saigon, a "brilliant liar." But that charge was not as important as the fact that Zorthian was there, on the podium, gamely defending the government's performance and critiquing the performance of the press.

Dean Phillips, a much-decorated, several- times-wounded veteran who now works as a lawyer for the Veterans Administration, said he was anti-war when he got home. But he has just retrained as a reserve officer in the 101st Airborne. Why? He thinks the volunteer army is even more inequitable than the Vietnam draft; he wants a draft-without-deferment enacted. In the meantime, he fears minorities will suffer even more disproportionately high casualties in any new "shootout" and he wants to "back up what I think in my own way."

Which brings me to Angel Almedina, a Vietnam infantryman who signed up at 18 and now runs a psychological outreach center for Vietnam veterans in Manhattan. Angel is short and chubby, a Hispanic with shoulder-length black hair, a voice of authority and a whirling-dervish oratorical style. He did his number only a few feet away from the raptly attentive, ramrod figure of former wartime ambassador to Saigon, Ellsworth Bunker, now over 80. It went like this:

"We're grown men--I'm 34--and a lot of us are hurting bad. But we're going to save each other. So if you want to be part of it, America, come with us. If not, look out. Because we're going to set some policies.

"In the next 10 years, there's going to be another war. But we got enough of us around here to tell you that my son is going to go when I (expletive deleted) decide. And it better be to a good war. In fact, if it's that good--I'm going."

That may not be the definitive expression of the real Vietnam syndrome. But its electrifying effect on a Vietnam-related audience distinctive for its diversity was enough to make you wary of the stereotypes.