A friend of mine was shot in the leg in Vietnam eight years ago. The 1964 war had not yet reached the full-scale peak of American involvement, with search-and-destroy operations and massive bombing and defoliation, but the United States already had 15,000 advisers in strife-torn Southeast Asia. America's longest war was already well underway.

My friend still journeys weekly to a veterans hospital for treatment, one of the hundreds of thousands of casualties in a bloody, senseless conflict that, after 12 years of direct American involvement, seems to be drawing to a close.

Disbelief is the only immediate credible response to President Nixon's television announcement that a cease-fire and truce have been agreed upon. Too many times before the conflict seemed to be ending, only to have hopes dashed by a new act of aggression by the American government.

The war's effect on the Vietnamese people dwarfs its other ramifications. Perhaps two million Indochinese have been slaughtered, wide swaths of Vietnamese countryside have been defoliated, and, in the South, a rural people have been forcibly relocated into teeming urban slums.

Sections of Laos and Vietnam are pockmarked with so many bomb craters that they resemble the landscape of the moon. Indeed, the people of Indochina have learned to live with the reality of twentieth century warfare.

But they have survived, and their revolution seems intact. It seems only a matter of time before their struggle to build a humane and just society is realized across all Vietnam. The greatest military power in the world has found it impossible to crush a peasant revolution.

Another friend of mine was on the 1970 drive into Cambodia. His company ran into elements of the North Vietnamese Army holed up in a Cambodian village, and they called in massive air strikes. As American fighter-bombers screamed in at tree-top level. North Vietnamese soldiers stood calmly in the center of the village, firing rifles at the planes. People like this could never be stopped by mere technology.

But the struggle also had far-reaching effects in American society. Growing numbers of Americans, bewildered by the discrepancy between their nation's professed ideals and its actions in Vietnam, questioned first their country's foreign policy and then its entire way of life.

The demonstrators who joined in increasingly militant antiwar actions from 1965 onward were only a portion of this number. Other Americans stayed at home in Dayton and Indianapolis, but doubts clawed at their idealized version of their nation and its government.

The war opened deep gaslies in the fabric of American society, reintroduced massive dissent and at times rebellion, and helped for many to undermine the basis of the American social order.

Reverberations emanating from the bloody conflict will continue in its aftermath in both Vietnam and America, and their eventual effects are impossible to discern. But this week the killing will stop, and after 12 years, that seems like an impossible dream come true.