Saigon, in its final moments, was a hellish tableau of smoke and the lightning pulses of artillery fire. Waves of refugees heaved in contrary directions around the besieged city, unsure whether remaining in Saigon meant safety or certain death. While big 130mm shells blasted in from across the Saigon river, Commander Kiet's North Vietnamese Army forces directed their rocket and artillery bombardments at Tan Son Nhut airport, where less than 24 hours before, the US had been flying the last frantic airlift, evacuating Americans and their Vietnamese helpers. Some of the last servicemen killed in the Vietnam war perished in the assault on Tan Son Nhut airport by Commander Kiet's Corps 3.
The officer was surprised that the South Vietnamese army only put up scant resistance. "We encountered some enemy tanks. But when we fired at them they surrendered, and the men tried to escape. They jumped out of their tanks and began stripping off their guns and uniforms - everything down to their undershorts - and running away.
"Later, a mother came to us and pointed out a man walking down the street in an undershirt. `Why are you arresting so many soldiers but not their general? See, he's getting away,' she told us. He was a top general," recalls Kiet.
He is a slight, wiry man, now in his sixties, with black hair sprouting stiffly, almost in salute. Unlike many US Vietnam veterans who are still dogged by the trauma of the conflict 20 years on, Commander Kiet is reluctant to speak of his emotions. I ask him how he felt entering Saigon, and he replies by reeling off the names of various divisions and corps and showing me campaign maps with vectors of invading columns closing in on the embattled city. "We didn't suffer too many casualties, except in battle," he adds pointlessly.
He is a career soldier, and after reunification, fought in Vietnam's abortive offensive against the Khmer Rouge in Cambodia. He retired shortly after, a topic he is also unwilling to discuss. Many Vietnam veterans were dispirited by Hanoi's brief dabble in expansionism.
Instead, he switches the topic to William Shakespeare, one of his favourite authors, and one has the impression that if Commander Kiet had not been swept up in Vietnam's wars against the French and the Americans, he would have been an excellent scholar, happier with his books than leading men into jungle combat. "The difference between the French and the Americans is that the French would only attack us with two planes, and the Americans would use more than you could count," he says. "They were both fierce enemies, but they were not fighting with a purpose the way we Vietnamese were."
Back on 26 March 1975, when Kiet first received orders from Hanoi to move his forces from their hideout in a honeycomb of caves and tunnels in the central highlands towards Saigon, he was elated. "I was floating in the sky. I had thought we'd have to fight for another two years more," he says.
After the fall of Danang in late March, the Vietnamese liberation army swiftly gained control of the highlands and the coast. "We attacked and occupied many towns, and people in these towns were sometimes afraid of us, suspicious," he says.
"But it wasn't like that in Saigon. On the way in to the airport from Hoc Mon [about 12 miles north-west of the city] the houses were all shuttered and closed. We had to go back for reinforcements along the same road, and this time the change was astonishing. People were rushing up to our men, giving them food, cigarettes, flowers and asking for news of their brothers. Nearly every family had someone fighting with our revolutionary forces."
By late morning on 30 April, Commander Kiet's column had pushed deep into Saigon's centre. "We had orders for a small group of our men to occupy the US embassy. But by the time we reached there, it was deserted. The last American helicopter had flown away, and after that, I guess everybody just ran away," he smiles.
Although Commander Kiet's family were only several miles away in Phu Dinh, a western suburb, he wasn't given leave for another 10 days. "We lived on an island. And when I crossed the bridge, I realised that I'd forgotten where our house was. Remember, I'd been away fighting for 30 years. Neighbours had to show me the way, and by the time I reached my family there was a great, joyful crowd with me."
These days he is helping the Ho Chi Min City Veterans Association prepare for the 20th anniversary parade, making sure that his old comrades are given decent seats for the fireworks and military parade.
Finally, he confides, "No, I don't have any nightmares, the way you hear these American soldiers did. Perhaps it's because we were fighting a just war and they weren't." He pauses. "But I'll never forget digging the graves for so many of my comrades. No, that I'll never forget."
These past three weeks, it has all come back for Ian Stirton. He is 49 now, an official of the Federal Election Commission, a quintessential Washington functionary. But he is also, and forever, a child of his generation. Twenty years have passed since that helicopter lifted the last refugees off the roof of the Saigon embassy, etching a final image of American defeat in Vietnam. But for Stirton and every other survivor among the nearly 3 million Americans who served there, the publication of a single book, Robert McNamara's In Retrospect: The Tragedy and Lessons of Vietnam, has sliced through two decades as though they had never happened.
It began for Stirton in 1968, that most baneful year of the American century, convulsed by the assassinations of Martin Luther King and Bobby Kennedy, by Vietnam and the breaking of LBJ, by the Chicago convention and riots of every hue. America seemed on the verge of coming asunder. He was a college graduate living outside San Francisco and "trying to be a too-late hippie, I suppose". Then came the call from back home in Michigan.
"I knew right away it was the draft notice. I thought about trying to get out of it. Most of my friends thought the war was wrong. My family was relatively progressive-thinking, and if I had refused, they probably would have supported me." But Stirton chose what he calls the "easy route", the line of least resistance. His country had called, and he obeyed.
First he went through basic training, then, that autumn, he was assigned - not to Vietnam at first, but Germany. "Oh wonderful, I thought, I've escaped."
At the beginning of 1969, however, orders arrived for him to go to Vietnam. Stirton got there just as US involvement approached its peak of 543,000 troops on the ground that April. When he landed at Cam Ranh bay, the tropical climate hit the northerner like a wall: "It was incredibly hot, I almost couldn't breathe, I didn't know how I would survive."
Stirton was attached to a signals detachment at II Corps headquarters, at Nha Trang on the coast. "They wanted someone who could keep records, and I was very fortunate, they were just picking people out. That day the gods were good to me."
Naturally, he had colleagues who died - who in Vietnam did not? But Stirton missed the nastiest part, infantry duty. In early 1970 his standard 12-month tour ended. He returned home with no resentment or dislike of the Vietnamese, just a vague sense of futility: "I didn't feel emotional about it. That came later."
But as he talks, the emotions do start to burn through, a sense of frustration, of wasted passion and wasted years. In 1978, he helped start Vietnam Veterans of America - but the veterans' movement has disappointed him. Perhaps in part because he didn't see frontline combat, Stirton has made no fetish of reunions.
"Vietnam was a different kind of war. People served at different times, had different tours, different duties. There wasn't much coherence to units. Sometimes I feel sorry for them - just imagine going to a Holiday Inn someplace for a reunion, and then you don't even recognise them."
These could be the musings of almost any man approaching 50, who realises he will not make it to the top of the greasy pole. But McNamara's book has reopened the wounds, leaving Ian Stirton "astonished at the passions conjured up in me by old film clips of the war and the p
And no player more than Robert McNamara, Defense Secretary of presidents Kennedy and Johnson.
"He's clinical, almost android, a quality's missing with him. He approached the war with numbers and charts. He used them to show there'd be light at the end of the tunnel. Of course there wasn't. But I'm glad he wrote the book, he was obliged to."
Stirton does not scorn those who manoeuvred to escape the draft; indeed, he says those who went to prison for their convictions as conscientious objectors were genuine heroes. "The ones that get my gander are the ones that found a loophole to escape service, but claim to have supported the war." Presidential candidate Phil Gramm and others, please note.
But most important, will the McNamara mea culpa, an old man's effort to salve his conscience for events of a quarter of a century before, finally purge America's soul of Vietnam? "To get over Vietnam," says Stirton, "the country must forgive those who got us into it"; and implicitly, McNamara is seeking this forgiveness. "But we won't come to terms with it until we die."