Since the searing spring day in 1968 when a grenade blew away his legs and left only a stump of his right arm, Max Cleland has been on what he calls a long and discomforting search for meaning. He has wondered about the purpose of his time in Vietnam, the lessons of his wounds, the reasons for his survival. For seven minutes on Thursday night, when he rolls his wheelchair to center stage at the Democratic National Convention and introduces his friend John F. Kerry to the nation, Cleland thinks he will be closer than ever to answering those timeless questions.

It promises to be the most emotional scene of the convention: the gaunt presidential candidate from Massachusetts stooping to embrace the broad-faced triple amputee from Georgia -- fellow Vietnam vets and former Senate colleagues, both encircled by the aging warriors they call the "band of brothers," including the Swift boat crewmates who served with young Lt. Kerry along the Mekong Delta 31/2 decades ago. The imagery is only a metaphor for something more profound, Cleland says, a culminating moment of personal and generational affirmation that sharply defines Kerry's rise and lends significance to the unresolved struggle of Cleland and many other Vietnam vets.

"John Kerry is really the tip of the iceberg, and the iceberg under the surface is the unconscious sense of lack of resolution of the Vietnam War," Cleland said in an interview Tuesday after taking part in a ceremony honoring veterans at Bunker Hill. "His success is like a validation of all this angst, storm and stress, and search for meaning, for people of his generation, not just for veterans, but especially for veterans because he personifies and embodies our own experience."

Cleland devoured a dripping cheeseburger at the old Warren Tavern as he spoke, his legless body perched snugly on a worn wooden bench. His longing for validation was echoed by many members of Kerry's old crew, who have been omnipresent in Boston this week and escorted the candidate as he made his way into town on a water taxi Wednesday afternoon.

"All of us have been waiting for this moment with John Kerry for 35 years," said Wade Sanders. "It has brought new meaning to our lives."

"Why did we live through this?" asked crewmate Del Sandusky. "Why are we here? For what is happening now."

John Hurley, another Vietnam vet who helped organize the band of brothers for Kerry during the winter primaries, said, "This is not just a campaign, it is a homecoming."

By no means do all veterans feel that way. A rump group of Swift boat veterans from other crews has expressed skepticism about accounts of Kerry's exploits. Some vets cannot forgive Kerry for protesting the war when he returned home and for testifying before Congress in 1971 about what he called atrocities committed by U.S. troops. And Republicans have tried to undercut Kerry's war experience by questioning, among other things, why he cut short his tour of duty after receiving three Purple Hearts for relatively superficial wounds. Cleland, from his wheelchair, finds particular force in countering that line of attack with a quote from Shakespeare's Romeo: "He jests at scars that never felt a wound."

The extent to which Kerry has embraced his Vietnam story and used it here in Boston, where a veterans caucus attracted 500 delegates on Monday and Cleland draws standing ovations at one delegation meeting after another as a revered speaker, has provoked weariness in some quarters. "I don't think they mentioned it this much at Woodstock," comedian Jon Stewart said of the Vietnam War in an interview with Katie Couric on NBC's "Today" show Wednesday morning. "I keep expecting to hear Buffalo Springfield." But for decades, Vietnam vets have grown accustomed to large segments of the public growing tired of them and wanting to move on, so a touch of sarcasm is not going to stop them now or make Cleland worry that they are overdoing it.

Kerry is not the first Vietnam vet to be either major party's presidential nominee -- Al Gore served "in country" as an Army journalist -- but he is the first to make it a central theme of his candidacy, and that, Cleland said, makes all the difference.

"I campaigned for Al Gore, campaigned hard for him, beginning in Iowa in January 2000. But there was no magic," Cleland said. "No emphasis on veterans. No organized veterans effort. As a matter of fact, Gore didn't even talk about it. And there was no band of brothers out there. This time it's the real deal. Kerry knows from whence he came. And all of that comes in the context of the search for meaning for veterans and the way meaning is being stripped away in Iraq. No weapons of mass destruction. No nuclear weapons program. No ties to al Qaeda. Okay. Okay. You can't call back those thousand kids who are now dead. You can't call back those arms and limbs over there at Walter Reed [Army Medical Center] that are now being fitted. That is what is so terrifying for the veterans of Vietnam. . . . I'm a student of history, and I can't think of a war in American history that had less meaning than Vietnam. And to sit and watch the meaning being stripped away again."

With Cleland, especially, the political and personal this year seem inextricably linked. "His resurrection has also been my personal resurrection," he said of Kerry's campaign.

It was only two years ago that the 62-year-old from suburban Atlanta was defeated in his bid for reelection to the Senate and fell into a chasm of despair. Whatever rage he felt toward Republicans for running a campaign ad linking him to Saddam Hussein and Osama bin Laden, and questioning his patriotism for voting against a version of the homeland security bill, was dampened by a life-numbing sensation that any purpose had been drained from his existence. He did not have the energy to get mad or get even. His fiancee, Nancy Ross, recalled that the low point was not election night, when he lost to Rep. Saxby Chambliss (R), 53 percent to 46 percent, but rather the morning of Jan. 6, 2003, when the next session of Congress opened and Cleland was at home with nothing to do. "From that point on, it was hard -- very, very hard," Ross said.

Kerry, Cleland said, was among the first friends to call him after that defeat, and kept calling for weeks thereafter, urging him to "get back in the game."

"He said, 'Max, come join me, help me turn this country around,' " Cleland recalled. "I said, 'John, I will when I can.' "

It took him six months to recover from the psychological wounds of his defeat, and when he was ready he headed out to Iowa and went to work. Week by week his energy and sense of purpose increased. His appetite was back, for food and people and work. He tooled around Iowa with such force that the wheels came off his wheelchair one day in western Iowa and he had to call across the border to the Department of Veterans Affairs hospital in Omaha in search of repairs. When a bureaucrat there told him that he was not in the system, Cleland, who was head of the Veterans Administration under President Jimmy Carter, cackled and shouted with glee, "Sweetheart, I am the system." He was back.

There was an evening in Des Moines in the dead of winter when Cleland realized that the fire was blazing inside him again. It was four degrees below zero when he headed over to Bakers Square for dinner. Sanders and Sandusky and the Swift boat guys were there, along with the Bolanos brothers of El Paso, four brothers who served together in Vietnam, and Kerry's Vietnam vet friends from Massachusetts, who called themselves the dog hunters and brought with them at least four vets they found at a Boston homeless shelter. Cleland pulled out his American Express card and paid for dinner for the whole crowd, and it was then that he recited parts of the well-worn St. Crispin's Day speech from "Henry V" and dubbed them the band of brothers.

Cleland had a sense then, long before the national press corps realized it, that Kerry could win Iowa and go on from there. "What organization has targeted veterans before? Nobody," he recalled. "But John Kerry did. And when he accepts the Democratic nomination Thursday night, a large part of the reason will be because of that."

When Kerry asked him to give the introductory speech on Thursday night, Cleland began shaping his thoughts. It was because of Vietnam that Cleland was handed the assignment, and he decided not to steer away from Vietnam as he put together the speech. Ten days ago, using the chicken-scratch cursive scrawl of his left hand, he began writing on some hotel stationery in Memphis. He kept writing until he had a draft that Ross could transcribe onto a computer. Then it went through three Kerry speechwriters and back to Cleland, who refined the final draft. The themes are simple: the Swift boat, the young skipper, the trust of his men, the band of brothers, the call to service, the quiet character, the affirmation of a generation, the skipper for the ship of state.

Cleland has a soft, deep, modulated voice with only a hint of the South. It evokes a radio voice from the past, which fits with his notion that he will be delivering a fireside chat to the convention hall and to the people back home. "I don't want to scream. That's not me," he said. "It'll be calmer and quieter and probably more emotional and intense than maybe I'm even comfortable with. But I think it will liberate my friend John Kerry. . . . I hope I can get through it without choking up."

Former senator Max Cleland (D-Ga.), who introduced Sen. John F. Kerry at a fundraiser in April, will again introduce his friend and fellow Vietnam veteran at the convention.A dozen of Sen. John F. Kerry's Swift boat crewmates from the Vietnam War accompany him on a ferry across Boston Harbor on their way to the convention. Story, Page A28.

Max Cleland with the Bolanos brothers, from left, Louis, Rick, Ben and Bill, at the Bunker Hill Monument. The brothers served together in Vietnam.John F. Kerry supporters, from left, Jim Rassmann, Fred Short, Drew Whitnow and Wade Sanders, who are among a group of Vietnam vets called the "band of brothers," attend a Salute to Veterans event at Bunker Hill.