TWENTY YEARS AGO this month, in Tam Key, Vietnam, I stepped on a land mine. It was a type we called a "Bouncing Betty," because when you stepped on it, it bounded into the air and exploded waist-high, so that it would do maximum damage. My left arm was blown off; grevious damage was also done to my right arm, both buttocks, both legs and both feet. Five of the men in my platoon were wounded along with me.

Within a four-week period after that, my platoon, Delta 1-6, was destroyed as a fighting unit. All but seven men of my platoon were killed or wounded, and the platoon, which was my family and my responsibility, ceased to exist as a fighting unit. I had given my all to Vietnam. I was proud to have been an Infantryman. I was proud of my men. I wept when South Vietnam fell.

So I was carrying a lot of emotional baggage when I returned to Vietnam for the first time last August, as part of a team sent by President Reagan to explore greater cooperation with Vietnam on a range of humanitarian issues. The leader of our group was retired Gen. John. W. Vessey Jr., a former chairman of the joint chiefs of staff. I was included because I am head of prosthetic services for the Veterans Administration. My job was to study the needs of disabled Vietnamese and see how we could help, particularly in the area of prosthetics. It was a trip that changed the way I think about Vietnam -- and maybe about America, too.

We let down through a clear sunny sky. Hanoi was off to the left. As we descended, we could see "Uncle Sam's Duck Ponds," GI slang for bomb craters, scattered across the landscape. I was surprised at the large number, and by the fact that they hadn't been filled in so many years later. Some were spaced haphazardly, others in neat rows spread from the American aircraft that had dropped them 15 or more years ago.

Flying into Hanoi was a confusing experience for me. When I first got off the airplane and stood on the tarmac, I was surprised and slightly embarrased to realize that my knees were weak and my hands were trembling. The adrenalin was pumping through my body and I felt the way I had long ago as I waited for the helicopters to take us into battle.

I could not surpress the feeling that I was in enemy territory. I was surrounded by North Vietnamese. Theshock of this after two decades was strange and unexpected. "What the hell am I doing here?" I asked myself. I had lost my arm fighting against Hanoi! In the years since, I had stayed angry at the Hanoi government for a number of reasons: their mistreatment of the South Vietnamese, their meanness on the POW/MIA issue, their arrogance and intractability on everything to do with America, and the simple fact that they had won the war.

And yet, driving from the airport into Hanoi, that hard edge of hatred seemed to soften. So little had changed in this land in 20 years. The women wore the same black pajamas and conical hats; bicycles still clogged the roads; water buffalos toiled in the rice paddies; fish traps stood at every drainage point in the fields and ditches; children played alongside the road; adults squatted in the doorways of their dwellings.

Here and there along the road, I could see cemeteries, graveyards for the soldiers who died in the war with America, each tombstone bearing a large red star.

We crossed the Red River on the bridge next to the one so frequently bombed during the war. It had taken 20 years but we were finally in the city limits of Hanoi! The city looked poor but reasonably neat. It could be called shabby. Streets, curbs, sidewalks and buildings are in need of repair. None of the buildings was taller than the trees. In the tropical heat and humidity, the entire city looked faded. But it takes money to keep paint looking good and this is a desperately poor country. According to the United Nations, Vietnam ranks 162 out of 164 countries in the world in per-capita income.

What I saw over the next few days turned my thinking about Vietnam upside down. We checked into the government guest house and were allowed to go where we wanted in the city. What happened to me, to put it in the simplest terms, was that I began to see the Vietnamese as a people.

My impressions of Hanoi were of an impoverished city, one drained of all resources by 50 years of war. A city too poor even to generate much trash. The North Vietnamese had finally won their war, but at the expense of consuming practically everything they had. A true Pyrrhic victory! Their problems were compounded by an economic policy which for the last 15 years was, by their own admission, a dismal failure.

The signs of poverty were everywhere. Women stood in line to buy a single smear of lipstick; street vendors used hypodermic needles to refill ballpoint pens; fixing flats was a constant activity on the streets. There was very little soap in the country (which perhaps accounts for the gray drabness of the clothing). Cigarettes were sold one at a time. Practically no one had a watch, so they all seemed to depend on the big clock on the main post office for telling time. What a sound it made. Not a bell but a gong.

We often walked in the park observing the people and in turn being observed by them. The kids were fascinated by my hook. They gathered around us, their faces full of curiosity and wonderment. They followed along for a short distance until their parents called. I was fascinated by the number of fathers who had their children on outings or spins around the lake. I did not expect to see this from hard-core Vietnamese. Maybe I hadn't imagined that these men I had hated for so long could love their children. That is what war does to us: It prevents us from seeing our enemies as human beings. But there was a great deal of love and pride evident in the faces of these Vietnamese fathers.

I walked over to the lake to see what the water looked like. I had watched a father squat by the edge and cool himself and his child with water he scooped up in his hands, and I was curious whether the water was clean. It was filthy: cloudy with the look of sewage and run-off from the gutters. I learned later that malaria and other infectious diseases are rampant throughout Vietnam. And I thought: The Vietnamese, my old enemies, suffer the afflictions that plague so much of the world -- polio, typhoid, diarrhea, the whole host of microorganisms that inflict mankind.

Because the Vietnamese are so poor, they lack the medicine to combat disease and infection. In one operating room we observed a 7-year-old girl with polio being prepared for surgery. There was no disinfectant on her skin or in the operating room and there were no antibiotics. The infection rate in the operating rooms was over 50 percent, we were told. To put this in perspective, the international standard which countries try to achieve is 3 percent. And I thought: this Vietnamese girl's mother and father don't love their child any less than I love my own two daughters.

One night I walked into a cafe with Bill Bell, a colleague who speaks Vietnamese and has been coming to Vietnam since 1973 as part of the official team that has been trying to recover POWs and MIAs. A group of about 15 older men were sitting around a couple of tables. They stopped talking immediately when we entered and watched us suspiciously as we walked to the bar. "Old cadre," remarked Bill, as we leaned against the teak bar.

Bill told me about one old veteran he had met a few years ago who related his travels along the Ho Chi Minh trail. During one trip, while driving a truck full of supplies, he had been strafed by American planes three times. Each time the bullets punctured his tires. He did not have any patching material so he improvised by hunting around the jungle and killing frogs. He skinned the frogs and used the hide to patch the tires.

Bill told me other stories; of editorials in the Hanoi newspapers raising hell with the government for not living up to the promises made to its veterans. The Vietnamese vets were complaining that they were not getting prosthetic limbs to replace the real arms and legs they had lost while fighting for their country. And younger veterans were complaining that the older veterans had all the good jobs.

I knew exactly what those Vietnamese vets were talking about. Certain problems are universal in nature, and veterans of any country voice much the same type of complaints. And I realized that I was beginning to feel an odd sense of kinship for their problems.

The odd thing was, the people I met seemed to genuinely like us, too. When we were out walking, they usually assumed we were Russian, since there are plenty of Russians around, and they seemed wary of us. But when they learned that we were Americans, their coldness turned to friendliness and curiosity. Maybe it's that we all share the same horrific experience of the Vietnam War.

This sense of kinship bothered me, to be honest. I had spent 20 years thinking of the North Vietnamese as the murderous ghouls who degraded our dead soldiers by holding them as ransom. Like my fellow Vietnam vets, I believed that they received some perverse pleasure from torturing the unfortunate families of gallant American men lost in battle. I hated the Vietnamese and believed they hated Americans just as much.

But here I was in the middle of Hanoi relating to these people as human beings -- discovering that I did not hate them as people. What was even more unsettling was that these people did not seem to hate us. As I walked around the lake in the evening or in the hot humid noonday sun watching the busy streets full of Vietnamese I felt a sense of freedom. Not politically but spiritually. I was actually enjoying myself for the most bizarre of reasons: I was taking a walk in Vietnam and I wasn't on guard for my life.

As a soldier in Vietnam 20 years ago, I had always wanted to be able to take a walk, to go for a stroll and look around without having to worry about getting shot or blown up by the Vietnamese. Now here I was in the middle of Hanoi, among friendly people, having a good time. I could relax. The war was over.

One evening, the Vietnamese delegation hosted a dinner for us. At the dinner I spoke to a Vietnamese official. He represented to me the quintessential North Vietnamese. He had been a prisoner of war under the Japanese, he had been shot in the stomach in 1952 while he was a Viet Minh fighting the French, and he was in charge of Clandestine Affairs in Urban Areas in the fight against the Americans. His brother was killed in a B-52 raid in 1972. Surely this man would hate me.

As we relaxed and conversed in comfortable surroundings I thought to myself that my dinner companion was no pilgrim. He was a hardcore soldier who had been fighting for his country's freedom from foreign domination all his life. Whether I agreed with his political philosophy or his definition of freedom or not, I respected the man for his determination and sacrifice. He had fought hard because he had wanted his countrymen to have a better life.

So I began to ask myself: Who will help these people achieve the goals they fought for so long and hard? Certainly not the Soviets. We saw nothing -- in any area of civilian life -- that the Russians have done to help the people of Vietnam achieve that better life. The North Vietnamese know they need help from someone. What country is rich enough to help them? And what country, in their eyes, owes them that help?

For years I have been reading about Vietnamese claims that we owe them war damages for what we did to them. I thought they had it backwards; my concern had been with the damage Vietnam had inflicted on America -- the dead and wounded, the POWs and MIAs, and the psychological damage inflicted on literally millions of other Americans. I didn't pay much attention to their demands for help.

Americans are a generous people. When we finish our wars, we usually try to help the other side back on its feet, no matter how many casualties we suffered or how hateful our adversaries. We helped create the modern economic miracles of Japan and Germany. But for Vietnam, we have had nothing. And if we're honest, we know why. It is because they won the war, and we still hate them for it.

When we left Vietnam our delegation recommended that humanitarian aid be provided to Vietnam by non-governmental organizations. As medical experts we knew this was the right thing to do because the medical needs are enormous. We did not like the politics of Vietnam but we liked the people. I came to believe that they deserved the assistance of the people of America. There will always be differences between our two countries, but there is a lot of common ground to work with.

Let me put it another way: Twenty years ago, when I lost my arm in Tam Key, I thought that I was fighting for the people of Vietnam. Today, although the government in Hanoi is not what I would like, the people still need our help. The North Vietnamese we fought and the South Vietnamese who were our allies are all under one government now. There are hundreds of thousands of our former friends and enemies who were left disabled by that war. They all share a common plight now. Do we leave these people handicapped with no hope for rehabilitation, no hope of recovering either physically or economically? Or should we try to help them?

Any soldier who has been in combat knows that there comes a time after the battle, when the smoke has blown away and the dust has settled, when you must lean down and give your foe a hand. For in that moment of generosity, the war is truly over.

Frederick Downs is the author of two books on his experiences in Vietnam, "The Killing Zone" and "Aftermath." He is presently the director of the VA's Prosthetic and Sensory Aids Service. He was awarded the Silver Star, four Purple Hearts, the Bronze Star for Valor and the Vietnamese Gold Cross of Gallantry.