The War We Still Are Fighting : AFTER THE WAR WAS OVER: Hanoi and Saigon, <i> By Neil Sheehan (Random House: $17; 131 pp.)</i>

What we Americans think we know about the Vietnam War has been delivered to us almost entirely by journalists: the network TV correspondents who zapped those panicky wobbling-camera shots of combat into our living rooms each evening after dinner; the newspaper photographers who engraved in our minds images of a naked, running, napalm-burned child; and the books of such magazine and newspaper writers as Michael Herr, Bernard Fall, and David Halberstam.

Early on, these reporters taught us not to trust what politicians (e.g., Johnson and Nixon) and soldiers (e.g., Westmoreland and Calley) had to tell us about the war. And so by the time film-makers such as Francis Ford Coppola and fiction-writers such as Tim O’Brien began to grapple with this material, they flashed their artistic licenses as if to say that their impressions of the war were as close to the truth as they could come.

“A Bright Shining Lie,” Neil Sheehan’s 1988 account of the rise and fall of John Paul Vann, “America’s Lawrence of Arabia in Vietnam,” directly concerned itself with the difficulty of ascertaining the truth about the Vietnam War. The truth was Sheehan’s preoccupation in his three years in Vietnam as a war correspondent in the 1960s and as the reporter who “obtain(ed) the Pentagon Papers, the official secret archive of the war, for the (New York) Times.” A powerful narrative composed in lucid prose of measured intelligence, “A Bright Shining Lie” gave its readers a sense that an essential understanding of the war was possible after all; excerpted in The New Yorker, the book won both the Pulitzer Prize and the National Book Award.

Recounting Sheehan’s 1989 return to Vietnam, “After the War Was Over” renders detailed portraits of Hanoi and Saigon today. Sheehan’s project is by definition impressionistic--the volume’s 131 pages give it a biblio-anorexia we more often associate with poetry than with journalism--but here, too, the prose seems effortlessly to convey the texture and tone of truth:

The process of change that (General Voo Nguyen) Giap spoke about is called doi moi, or “renovation,” (literally “new way”). The subject dominated almost every conversation because life in Vietnam was divided into what had happened before doi moi and what has happened since. “Drunk with victory” was the phrase Vietnamese used to describe the mind - set of their senior leadership during the decade after the fall of the U.S.-backed Saigon regime in 1975. The period was seen in retrospect as a time of tyranny and waste, a heedless attempt to create a visionary socialist state in defiance of reality, a folly that compounded the troubles inherited from the war and drove Vietnam into bankruptcy.

Sheehan packs his paragraphs with information and analysis, so that to read “After the War Was Over” is to witness a gradual (but ingeniously efficient) assembly of “the big picture.” However, the most engaging and affecting parts of this book are the then-and-now snapshots of Vietnamese individuals:

Ly Tong Ba, general of the ARVN, was lying on his back under the water of a flooded rice paddy, trying to poke only his nose above the surface in order to breathe without being seen. He had learned the trick from the Viet Cong; the guerrillas had used it in the Mekong Delta to escape his armored carriers. He had just one soldier left--his bodyguard, who was lying beside him. Ba had managed to gather his staff and the division reconnaissance company and set off for Hoc Mon by foot, but his enemies had anticipated this move too and had been waiting in ambush along the road. “Shoot back!” Ba had yelled when the ambushers opened fire. No one obeyed him. “We lose now, General,” one of his staff captains said .

By the time I saw him in the summer of 1989 he was back up to 150 pounds and looked fit for his 58 years and spiffy in a navy blue Lacoste shirt. A tennis racket stood in a corner of the one-room apartment. Ba played frequently at Saigon’s once-exclusive Cercle Sportif. The place had been declared a public recreation center after 1975 and, like much else in a country that lacks funds for public facilities, was now dirty and rundown, but Ba joked that the tennis courts still had nets. He had a minor eye problem amenable to surgery and was going to do something about it after he got to the United States. He was waiting for the authorities in Hanoi to grant him an exit permit. His name was already on the list of those former re-education camp prisoners acceptable to the U.S. Government.

For the American public, the Vietnam War offered a profound lesson in the elusiveness of truth. Nevertheless, we continue wanting to be told the story of what really happened over there where American idealism got the hell beaten out of it. Sheehan’s theory is blunt: “. . . arrogance had rendered the American system witless, . . . the men in charge had made up their minds in advance and listened only to themselves.” But it is for the texture of daily experience in contemporary Vietnam that we must read Sheehan’s book, for the news it has to deliver to us about the consequences of our actions--then and now.

Sheehan’s achievement is a paradoxical one: His book evokes life in a country that seems even more distant from our shores than ever, but it also completes a crucial chapter that has been missing from American history. Sheehan’s sly title suggests to us how informed the current national consciousness is by this war that we stopped fighting more than 20 years ago. Even though we’ve been to Panama and Grenada and the Persian Gulf since the last U.S. helicopter lifted from the embassy roof in Saigon, we nevertheless know exactly which war he means--the one that forever changed America’s thinking about itself.

It isn’t really over in Vietnam any more than it is in the United States; citizens of both nations are still coming to terms with it. But in telling us this piece of the story that we’ve so desperately needed to hear--what things are like over there since we left--”After the War Was Over” helps us understand exactly what we did to the Vietnamese and to ourselves.

BOOKMARK: For an excerpt from “After the War Was Over,” see the Opinion section, Page 3.