"The enemy soldier appeared to be about 18 or 19. He had been hit in the worst, most painful place a man can be hit, in the place that is the center of so many aches, the ache of fear, of hunger, sometimes even of love. We feel so many things in our guts and that is where two 7.62-mm bullets had caught him . . . He had had ample time to feel pain and perhaps to realize that death was not decades, but only moments away . . ."

From "A Rumor of War" by Philip Caputo

MOSCOW - The buffet party has reached the point of pleasant satiation - dessert finished, digestion under way, talk of kids, schools, "trips out" (as in, "I'm going out to England," not as in, "I'm tripping out"). Unmistakably sweet, respectable domesticity.

Except over in that corner. There, voices rumbling, then cascading in short laughs are two guys off by themselves - Phil Caputo and another toughened journalist and they are trading war stories.

"We were expecting an attack, so the perimeter was pulled back a thousand meters to protect the airfield . . ."

". . . and then you could hear the machine gun . . ."

It is a uniquely American experience to be at a party and hear family talk out of one ear and out of the other, hear yarns of hilarious military zaniness and the ghastly sacrifice of the Vietnam battlefield. Never mind that this cube of capitalists floats on the umpteenth floor of one of the many slab-sided highrises where they domicile Americans in Moscow. This could be Bethesda, or Hybla Valley or Anyplace, U.S.A. We carry our culture with us.

And now that includes Caputo and his book, "A Rumor of War," which is a national best-seller. It was the July main selection of Book-of-the-Month Club and has been sold to paperback and optioned for a possible television mini-series.

All this is not hard to understand, even though it is a book about a subject that everyone thought America was sick of and wouldn't confront directly. Well, Caputo's book confronts it with the compressed energy and impact of a rifle slug. It is a modern classic of combat writing - a story of savage jungle fighting and the moral decay of Caputo himself - from nice, God-fearing suburbanite offspring (the kind of person you wouldn't mind at your buffet) to premeditated instigator of murder.

He serves it to you just the way he encountered it as a young Marine officer, stepping off a cargo plane at Danang airfield in 1965, part of the first contingent of American ground combat troops sent to Vietnam, and then surviving 16 months of duty there, much of it pointless.

"Forming a column, my platoon started toward its first objective, a knoll on the far side of the milky-brown sream. It was an objective only in the geographical sense of the word, it had no military significance. In the vacuum of that jungle, we could have gone in as many directions as there are points on a compass and any one direction was as likely to lead us to the VC, or away from them, as any other . . ."

When he got out of the Marines in 1967, he thought about writing a novel of the war. He had kept some notes here and there and had written fairly detailed letters to his parents. And he had written his memories, and his nightmares.

Remarks Caputo: "It's like Audie Murphy the most decorated American soldier of World War II, a western-movie actor, now dead says. "You never get over it. The things you see and learn in war become a permanent part of how you think."

For a few months after his discharge, he bummed through Europe "trying to get away from the war" without success. He couldn't escape it and he couldn't write well about it. "Hemingway once said it's difficult to write imaginatively when you know too much about something. It wasn't working primarily because I was emotionally too close to it." On his way back to America, he spent some time in England and there found the poetry of Siegfried Sassoon and Wilfred Owen, two who had seen war and written much about it. Today, 10 years after that discovery, Caputo still says with some amazement, "The emotions they felt were the same I had in Vietnam."

Not surprisingly, "A Rumor of War" begins each of its sections and chapters with quotes from Sassoon or Owen or others from an eclectic chorus of voices, ranging from St. Matthew to Howard Fast to a 19th-century Swiss-born general and military strategist named Baron Henri Jomini this dry observation - "The greatest tragedy is war but so long as there is mankind, there is war" - begins Chapter 12. Part Two, entitled. "The Officer in Charge of the Dead."

Once back home in Chicago, he got a job with the 3M Corp., writing promotional [WORD ILLEGIBLE] and working on a house paper. It was devastating. "When I left Vietnam, I wanted more out of life than life wanted to offer, it seemed - a tie, a suit and talk football scores. I thought to myself, I went through all that for this. He began to think he should go back to Vietnam. "I didn't want to go back, but it seemed like the only thing to do. I had more in common with Vietnam than the U.S.A."

Then he decided to become a reporter and return to Vietnam that way. He was hired by a Chicago Tribune editor who, like Caputo, was an ex-Marine with a love of Shakespeare. "I think he felt charitable." Within a few years, he was deep into local stories. "I covered every cheap murder and fire and boring speech by a Vietnam vet (here a big laugh) and learned how to write while doing journalism. Journalism teaches because it requires you to be concrete. I enjoyed the drama, because still then in the late '60s, it was wild, right out of Ben Hecht . . . . There was drama covering the cop beat of a big city at night."

Caputo helped probe Cook County nursing homes and vote-fraud allegations, and prizes started rolling in: a golden gavel from the American Bar Assn., and others.

And he was dating Jill Ongemach, half-German, half-Italian strawberry blonde who was three months older. Both Chicago suburbanites, they had dated as teen-agers (introduced by Jill's twin brother) and then fallen out of touch. She had a master's degree in library science and had lived in England for a year, working as a librarian on an American air base. She was trying to escape . . . whatever there is to escape in the comfortable lives that parents can sometimes offer their children. England hadn't worked out - "all the officers went with the English girls and I was very straight" - so she came home. "Why?" Her eyes widen, "because I was 26 and single and a woman . . ."

She ran into Caputo but it didn't take. And then . . . several years later, she stopped in at a bar after bikeriding all afternoon and there he was.

Something had changed. "It really struck me that evening . . . he's an exciting man." They were married, and soon there was a child, Geoffrey (spelled like in Chaucer," says Caputo, perfectly serious).

The war still tugged like a tide. "I'd be walking in the woods and without even trying, I'd say to myself that'd make a good ambush site. When the rain fell, it reminded me of the monsoons . . . the war had a grip and you couldn't get free."

He found himself swept by wild swings of emotion. "I was still dating Jill and we went to a restaurant and I looked around and saw all these people and I hated them with a murderous hatred . . . they were so fat, so normal! I told her, 'I'm getting out of here, I can't stand this.' She got it and we left." He discovered in talking to other vets that they had the same impulses.

He toyed with getting into the anti-war movement, went to a few meetings, and "one small rally," but was turned off by it. He detected a streak of intolerance. "I didn't like a lot of them. They were college kids with no experience of life and I didn't know how much was genuine anti-war and how much was just a kick." From the combat veteran, a sense of invasion - and observation.

"It was once again just like the Army, with its own values, its own jargon. I remember a guy trying to recruit me and it was just like the Marines - 'anti-war people are looking for veterans, a special kind of man, like you.' When he was talking to me, he was wearing buttons from demonstrations, just like a general's ribbons."

He felt more comfortable with the Vietnam Veterans Against the War because, "The people who had a real right to protest were the ones who had been in it." But even here, there was ambivalence, so much so that somehow he missed the VVAW's supreme moment, the march on Washington. When he discovered what had happened. "Emotionally I was very agitated that I had missed this - a real demonstration by vets and I was a vet."

So he decided to do something on his own.

"I mailed my campaign ribbons to President Nixon, together with a long and bitter letter explaining why I was opposed to American policies in Indochina. I thought, naively, that such a personal, individual act would have more effect than mass marches. About a month later, I received in the mail an envelope bearing the return address 'The White House.' It contained my medals and a curt note . . . which said that the Executive Branch of the United States government was not authorized to receive or hold military decorations, therefore, my ribbons were being returned to me . . ."

From the book.

In 1972, The Tribune moved the Caputos to Rome. There, he found other wars. While in Beirut covering one of the many outbursts of violence, he was captured by Palestinian guerrillas. His account of his six-day captivity wom him the George Polk journalism award for 1973. He covered the October 1973 Yom Kippur war.

Meanwhile, his ideas about the Vietnam book were slowly crystallizing. He had continued to gnaw at it, writing sporadically when there was time and inclination. The novel became some fictional sketches, then through the sketches he began to see more and more that he was in fact writing a masked version of what had befallen him.

In March of 1974, he was sitting with his recollections on the patio of their Rome apartment, a few blocks from an ancient street where Caesar's legions had once marched out. "Suddenly, I realized that the only solution was to write non-fiction. I saw the whole thing, each segment and the shape of it, and the moral tale as well."

He began writing furiously, setting down the story in longhand, then retyping it. The Caputos were moved to Beirut in November of 1974, and early the next year, he was sent to Vietnam to cover the final weeks of the war.

When the end came, he left in the last flights of helicopters. "Emotionally, the fall of Saigon (in April 1975) completed the circle for me. The war was finally over." He had the distance that Hemingway said was necessary. He returned to Beirut and plunged on, polishing the prologue and first section and a synopsis.A New York agent, Aaron Priest, read it and was positive there would be a publisher. "I knew now I had to write it anyway."

Soon, Beirut was ripped by the Lebanese civil war. "It was like a checkerboard and they were moving the pieces around . . . . one day the square was occupied by the Christian right wing and the next day by the Palestinian left wing."

On Oct. 26, 1975, he stepped into the wrong square. He was stopped by some Palestinian guerrillas while walking two blocks from his parked car to the Reuters agency to file a story. He had been stopped before, many times, but this time there was something very wrong. Caputo started to head back for the car, to get away. "I heard a bullet crack overhead" from somewhere, and then the Palestinians were waving at him and one man fired from his Ak-47. Caputo was hit in the arms and back by bits of concrete and ricocheting lead. He began to run and they chased him, firing. He was hit on the head by another chunk of concrete, fell and then scrambled up. The distance was closing rapidly. A bullet hit him in the right toes, and as he danced crazily toward a Christian barricade, a shell hit him in the left ankle, shattering it. "You feel no pain, you feel the impact." He was down and crawling, watching the blood pour out, seeing the burn marks in his boot where the bullet had gone in.

"I was getting near this barricade and maybe safety, but I was getting weak, too. I yelled, 'Come here.' They answered, 'No, you come here.'" He finally crawled to safety and was taken to a maternity hospital that had been turned into a Christian hospital. He had nightmares of getting killed in his bed. But after three days, a U.S. Marine colonel showed up dressed in civilian slacks, shirt, tie, sport coat and flak jacket, and took him out via a bullet-proof embassy limo. He flew back to the States in a military medevac in a plane "loaded with wounded and maimed U.S. troops who had been injured in various accidents while on NATO maneuvers."

Jill was sorry to leave Beirut. "I didn't realize this until I left Chicago," she said with the air of a person confiding a family secret . . . "I like La Dolce Vital. I thought to myself, 'Well, if it's got to be a civil war, how much better Beirut than Belfast. Even when we were evacuating Beirut, I was looking at the monuments and thinking, gee whiz.'"

It took well into 1976 for the wounds to heal. He spent the time writing, first in a bungalow the family rented in Key West, and then by himself, in a Montana cabin. Jill stayed behind, caring for the children (by now, a second son, Marc Antony, baptized in St. Peter's). She had plenty to do - The Tribune had designated him its next Moscow correspondent as soon as he was recovered. Her days were filled with planning and packing. "First we're lovers, then were a married couple, and then I'm a logistic officer." Her face opens in amazement. "When he told me I was a logistics officer, I thought, 'that's one of the nicest things.'"

He finished retyping the manuscript 11 hours before the movers came to get the family under way for Moscow. They arrived here last fall. It has been less than satisfying for them.

Jill: "He's a man's man. Here in Moscow, it's all so civil it's hard on Phil. There's no pub here. You guys don't run off here and there and cover stories. It's a real hardship."

Besides, the action was in the States, where the book was gathering momentum. This spring, when the Book-of-the-Month Club chose it as a main selection, they were virtually insured comforable money. To him, it was a chance to change his life. In June, he resigned from the newspaper, effective a few weeks from now.

They will move to Key West, a place, she says, of endless days of blue sky and sun. It's going to be good for them, she is sure. "He needs to wind way down. It's been a tough two years, one thing right after the other." A book-promotion trip for a month through the States in June seemed to drain him more. "He had awful nightmares when he came back, but he's better now."

He wants to try for the "timelessness" of literature, which to his mind is different from the timeliness of journalism. He wants solitude to grapple with the god of war. The second book, a novel, will be set in the Eritrean rebellion, which he looked at, and focuses on three Americans who find themselves caught up in it by design or accident.

"War serves as a social laboratory, where all the restraints and marks of civilization are gone, and in places like that, you are able to see men behave. You can see their characters much more clearly than in ordinary life.

Human behavior under pressure is a moral challenge, and many of us failed that test in Vietnam. We got so obsessed with being tough, we forgot there are other values beside physical bravery. I'm trying to get at what makes one man act well and one act badly."

At 36, having written a best-seller that may in time be judged an enduring classic, he is ready for the gamble of reaching out into the imaginary world and creating his characters from within his own mind. The still points in his world - and perhaps in ours, too, for that matter - have been war. "There's been so much war this century I think we're all infected with it." He remembers Walter Cronkite facing America each night with the Vietnam casualty figures projected behind him in neat rows of so many Americans, so many Vietnamese, so many Vietcong. "It made war a permanent condition of life, like the stockmarket tables."

He consoles himself this way: "Any honest book about war comes out antiwar. It has to."

And then, as he talks some more about "A Rumor of War" and his life, his mind flickers back to the last days of the American struggle in Vietnam. He is thinking now about the last two killed, two young Marines who died while guarding the embassy in the final days of the spring of 1975, a decade after Caputo stepped onto Vietnamese soil for the first time as a member of the first wave of troops.

"I read that one of the last two killed was 19. When I saw that, I realized that that Marine must have been a child of 9 when I went to war. Neither he nor his parents could have had an intimation that he would die in that war . . that little boy . . . their son . . ."