ASHINGTON --In this city of monuments in which I live there is only one monument that is not a monument to glory. It is the Vietnam Memorial.
Until that war, which ended 25 years ago today as the last American helicopter lifted off from the US embassy and the tanks of the North Vietnamese Army thrust into Saigon, all American wars had been good wars. They had been crusades, morally unifying experiences, beginning with the revolution to free the Thirteen Colonies from English tyranny and found the nation.
There had been deviations, of course. The war with Mexico in the 1840s had been a war of conquest and we had fought another war of conquest in the Philippines, our first imperial possession in Asia, at the turn of the 20th century.
But these had been pushed out of the American historical memory. Our monuments had always reflected the good American wars - a Grecian temple of worship to Lincoln, the godlike President who had kept the nation one through the agony of the Civil War; the Marines raising the Stars and Stripes over Mt. Suribachi on Iwo Jima in the ulimate of good American wars, World War II, when our cause had been the cause of humanity and we had crushed the most hideous of enemies, Hitler's Germany and Imperial Japan.
We had gone off to Vietnam in the halo of that triumph. The result had been the longest war in our history, the most divisive since the Civil War, and to commemorate it, this funereal monument of defeat and mourning was erected.
It is a wall of polished black granite inscribed with 58,197 names of the dead. The wall descends into the earth in a great V like a mass grave, the panels growing larger as one walks down into the grave, from a few names on the small panels at the ends of the V to the thousands that fill the big panels that rise above one's head at the V's sunken vortex.
Yet defeat can be as precious as victory if we learn from it, if we face the bitter but necessary truths that must be faced to redeem the lives of the 58,197 victims. And the most important of those truths is that we were fortunate to lose the war in Vietnam.
The catastrophe could have been worse. The same kind of mindset that sent the youth of Europe by the millions into the barbed wire and machine guns of World War I sent our infantrymen into the mantrap bunker complexes that the Vietnamese constructed under the canopy of their rain forests to kill our soldiers and wear us down.
The leaders we had acquired by the 1960s were men who had lost the capacity to grasp reality, men overcome by hubris as they contemplated their power. And we the citizenry, inebriated from the same cup, had followed them. In the spirit of John Kennedy's grandiose inaugural address, we saw ourselves as the new Romans holding back the barbarians at the frontiers of our beneficent empire.
Ho Chi Minh and his followers were pawns of the Soviets and the Chinese, ''the Sino-Soviet bloc,'' as the Army security-clearance forms termed them. And if we did not stop them in South Vietnam, the dominoes of Southeast Asia would topple one by one and Communist-inspired guerrilla wars would sweep the whole of the underdeveloped world until we were battling in Central America.
It was all delusions. The Vietnamese were no one's pawns and they never threatened us. They simply wanted us to go home and leave them alone. Ho Chi Minh had become a Communist as an accident of French domestic politics. Only the far left in France had favored independence for the colonies when Ho had gone there as a youth during World War I to seek help to free his country from French colonial rule.
The motivating force within him and those who became his disciples had always been nationalism. The Vietnamese are a people who will not tolerate foreign domination. They demonstrated that spirit by their willingness to resist us as long as it took, and to pay whatever price was required in blood to achieve the unification and independence of their land. In our delusions, we made them pay. By the end of the war we had killed a million and a half of those Vietnamese who fought us in the cause of their nation.
Our folly was not limited to the devastation of Vietnam and the neighboring lands of Cambodia and Laos. At home we were undermining our most precious possession - our constitutional republic with its rights and liberties embodied in law.
The system of checks and balances between the Executive, Legislative, and Judiciary branches which the Founding Fathers had crafted to perpetuate this ideal of republican government had been profoundly unbalanced. The power of the Presidency and the executive branch that had grown up under it since World War II outweighed that of the other two branches to the point of becoming monarchal.
The Watergate affair - when Richard Nixon and his henchmen attempted to rig a national election by burglarizing and bugging the headquarters of the opposition party, freely wiretapped anyone else they perceived as an enemy, and then paid out hundreds of thousands of dollars in hush money to obstruct justice - was a harbinger of the loss of our rights and liberties under an authoritarian state if the power of the Presidency had not later been humbled by defeat in Vietnam.
We have emerged a skeptical people who have learned the price of vowing to ''pay any price, bear any burden,'' as JFK had summoned us to do, in what he mistakenly imagined to be a call to greatness. We no longer march off as automatons to war. We are selective in our interventions, more realistic about our role in the world because we sense our limitations.
From the bestarred circle of the Joint Chiefs to the hardhats on a construction site, we now want to know whether the venture is necessary, feasible, what it will cost in treasure and in blood, whether there will be an end to it. Sometimes we are too timid, as we were in Bosnia and at the outset in Kosovo, when we might have saved so many lives by a willingness to intervene on the ground. But timidity in accepting casualties is understandable after 58,197 lives have been wasted.
Some would say we have become a cynical people, but I do not believe that. We have merely learned that doubt can lead to less harm than credulity. The worst folly now would be to forget, but the Wall helps us to remember. It is a holy place. Children grow quiet there as they sense its reverence. To reach up and touch a name is to see again the man you knew when you and he were young. And in their thousands, these names cry out for remembrance. The war in Vietnam must remain an adamant memory for us. We must never again send American soldiers abroad to die foolishly, and we must never again play God with another people who mean us no harm.
To remember Vietnam is to understand that we Americans are not the exceptions to history we once thought we were, rather that we share a fallible humanity with the rest of humankind. To remember Vietnam is to see our all-too-human capacity to do evil as easily as we can do good.
Neil Sheehan reported from Vietnam for United Press International and the New York Times in the 1960s, and he obtained the Pentagon Papers for the Times in 1971. His 1988 book, ''A Bright Shining Lie: John Paul Vann and America in Vietnam,'' won a Pulitzer Prize and a National Book Award. He's currently writing a book about the arms race and the Cold War.
