ON THE FRINGE of the recent Democratic National Convention in Boston, there was a miniconvention of a group called Veterans for Peace. Most of the 400-plus participants were Vietnam veterans, though there were smaller contingents of veterans of World War II, the Korean War, and the first Gulf War. But the most dramatic presence was that of a group of new kids on the block, veterans of the war in Iraq. These new veterans could come to have a powerful influence on our country. Iraq veterans undergo the same psychological struggles of all survivors over images of deaths , how much to feel and not to feel, pain and guilt from the deaths of buddies and their own behavior. Above all, war survivors hunger for meaning -- for some kind of moral judgment about their encounters with death.
In this quest for understanding, it turns out that Iraq veterans have much in common with their older compatriots who fought in Vietnam. Both groups were involved in a confusing counterinsurgency war conducted in an alien, hostile environment against a nonwhite enemy as elusive as he was dangerous. The result in both cases was an atrocity-producing situation -- one structured militarily and psychologically so that ordinary soldiers with no special history of violence or antisocial behavior were suddenly capable of killing or torturing civilians who were loosely designated as "the enemy."
A significant number of Vietnam veterans found meaning in opposing their war while it was in progress. The hearings on American war crimes and the throwing away of medals were their way of rejecting the war and holding not just themselves but their country accountable.
Their impact on the nation was different from that of other antiwar protesters because they were able to bring the Vietnam death scene directly to the American public, as John Kerry did in his 1971 testimony before a US Senate subcommittee, when he asked, "How we can ask a man to be the last man to die for a mistake?"
What Kerry and other antiwar veterans were contesting was the wartime tradition that in order to make sure the fallen did not "die in vain," one must rally round the flag, assert the nobility of the cause, and prosecute the war ever more vigorously.Instead, they invoked the authority of the dead to oppose rather than perpetuate the war.
This kind of alternative is by no means new -- it was powerfully expressed by writers surviving World War I and goes back as far as Homer.
Iraq veterans are beginning to express similar sentiments. In Boston they sounded not unlike their Vietnam predecessors. They emphasized the large-scale killing of Iraqi civilians by American firepower, along with their own widespread confusion. "We were lost. We had no idea what we were doing," was the way one put it.
These veterans formed a new organization at the convention, Iraq Veterans Against the War, modeled on the earlier Vietnam Veterans Against the War. It is too early to say how many will join this new group; much depends on what happens in Iraq and on the extent of antiwar opposition at home.
But there is already a personal and primal connection between veterans of Vietnam and Iraq: They are literally fathers and sons or daughters. Generational transmission of war experience has always had enormous psychological importance. Men who fought in Vietnam told me decades ago of having heard, on their fathers' knees, tales of courage and heroism in fighting the "good war." Those World War II fathers were often perplexed and angered by their sons' disillusionment with and bitter opposition to their own war. But Vietnam veteran fathers may have no such difficulty with the disillusionment of their children.
The sharing of an antiwar sentiment may indeed be a powerful bond. That was the case with an Iraq veteran, the daughter of a Vietnam veteran, who spoke at the meeting of the extreme chaos in which neither Americans nor Iraqis could be "protected" and of her constant question of "what we were doing there."
American soldiers fighting in Iraq are also saying things reminiscent of their Vietnam veteran fathers and uncles. The British newspaper The Guardian reported American soldiers as saying: "It's really frustrating cause I mean we can't find these guys. They shoot at us all the time, they run away, we try to figure out who it is, we interrogate people -- do they know who it was? No, nobody knows who it was"; and "This is the last place I'd probably ever want to die"; and "I don't have any idea of what we're trying to do out here. I don't know what the [goal] is, and I don't think our commanders do either."
These feelings arise from the war in Iraq. But the Vietnam experience hovers over everything; it is reactivated by what we hear about Iraq. In that sense a shared parent-child antiwar sentiment may come to reverberate throughout society. We have not heard the last of this poignant generational alliance.

Robert J. Lifton is a lecturer in psychiatry at Harvard Medical School and author, most recently, of "Superpower Syndrome: America's Apocalyptic Confrontation with the World."