I was a naval gunfire officer in the Vietnam War—a Navy lieutenant serving in the 7th Marine (Infantry) Regiment. I was among the Marines but not one of them. When they marched into battle I marched with them. When they got hit, I hit back.

If you’re in a close-range firefight, “hitting back” is easy because the enemy is trying to kill you and you can often seem him or his muzzle flash and the noise pierces your ears. The bullets seem to lash a whip beside your head, and you are high. You are way up there.

In such a fight the enemy is too close for naval guns or Marine Corps howitzers. The men on your side hit back with small arms and grenades.

But there is a different case. You and your comrades come under fire. The slugs crease around your ears and the mortar rounds thud in and blast dirt and sometimes death—but you can’t see the enemy. If you’re lucky you catch a flash in a treeline, or he sends out tracers (which he uses to aim his machine gun, but which you can use to aim at him). He’s far away—more than 300 meters, let’s say. What you throw back at him is the big stuff, which you control by radio communication with a ship or battery. You stand up, which is the exhilarating part, to see the fall of shot; then you adjust—add, drop, left, right—till you have the target bracketed. Then you pour it on, you “fire for effect.”

The problem is that the big weapons kill civilians, as they are still doing in Iraq today. Guns and bombs are more accurate now, but the problem is actually worse because the military seems to think precision is possible and because we are fighting in cities. And, as is painfully apparent in Iraq and Afghanistan, the big weapons and munitions create a hundred new enemies for every one they kill. Maybe because this is still going on, Vietnam is present to me every day.

After the war I wrote a novel called Neverlight about a naval gunfire officer whose job was to minimize Marine deaths by silencing enemy guns. American armies do not send troops into battle naked. They protect them with the three “supporting arms” of naval gunfire, artillery, and air power. I would never argue that we are wrong to do so. But there is a cost.

Neverlight was my attempt to create a true drama, fiction that was faithful to reality, about the tearing of the psyche that comes with controlling the big guns. Here is a united, integrated man; and this, some time later, is half a man, the half charged with keeping marine casualties to a minimum. Let no Marine die through my neglect. Here is the other half, the one charged with a full consciousness of what happens at the end of the trajectory of a 5-inch-54 naval rifle or a 105mm howitzer.

For many years I believed I could leave Vietnam alone because I had done all I could do in a novel about that war and the use of big weapons that characterized it. Years later I felt myself being pulled back to Vietnam. I think the reason was partly that going there was the most transforming—burning, flooding—experience of my life. But another reason, a part perhaps of the first, was the “tearing.” If you can’t stand the tear, you might leap to one side and cauterize the other. I have known men who do this. I think it is fatal to the soul and I have not done it.

This is what pulled me back to Vietnam, this determination to remain whole as I understand wholeness. It translates to a need to reach an honest understanding of the fighter’s duty and the stresses that change him. And having written a novel on the war I thought of writing a memoir, of exploring Vietnam through the lens of my own experience. But this time I would go beyond the main concerns of Neverlight, which were to set forth the moral conflict of a man wielding the big weapons, and of his wife’s progress toward moral opposition to the war.

I thought my own (true) story could provide the kind of history that sheds light on the present. And with 19 years’ experience as a reporter covering civil rights, the antiwar movement, and finally politics, I believed I could write a clear and objective account of the conflicts inherent in the American way of fighting. I thought of Francis Parkman’s pioneer soldiers marching through the woods at night in Montcalm and Wolfe, “lashed by branches they could not see.” A novelist’s detail or a historian’s? I thought of James B. Puller Jr.’s autobiography, which has all the force of the best fiction. A memoir must be shaped as art is shaped, and a novel that violates the truth cuts off its own legs. The difference between memoir and fiction, then, may not be quite so important as it seems. It is, nonetheless, a fundamental difference. Fiction is an open field for the informed imagination. It has its own constraints, but they tend to liberate the writer rather than to limit his or her scope and powers. A writer constrained by form is freer than one constrained by fact. Form in fiction is its own style of freedom. It is a river; you can swim from bank to bank, you can shoot the rapids, but you cannot crawl out; if you do, you’re dead, like a fish out of water.

It is freedom within boundaries and constraints that opens a writer’s opportunities to create the truest imitation of life.

In my intellect I agreed with Aristotle’s dictum that poetry (I read that to include fiction) is “more philosophic and of graver import” than history. Aristotle says that history tells what happened in the past. Poetic fiction tells what could happen at any time. But some nonfiction exceeds Aristotle’s estimate. Nobody can approach an understanding of the Vietnam War without reading the major nonfiction. These works convey more than “understanding.” Many of the best also arouse the strongest emotions—an awed respect for men like Puller; anger verging on fury when he was driven to suicide; incredulity and rage that Johnson, Westmoreland, McNamara, and their clown group could have been so wrong, so persistently, inexcusably, and fatally wrong, at such expense to the country and its youth.

Thinking about a memoir, not quite committed, I went over my notes from Vietnam, written in crude Spanish and Greek characters, in case of capture. I found them haunting, stirring, and incomplete. I had had little time to write them and often couldn’t write when time was there because of the monsoon. Many entries were perfectly unintelligible to me and some of the people were lost to memory.

But what fascinated and drew me in was the incompleteness. It seemed to rule out any account of my experience. It did something more important. It led me to a new appreciation of the power of implication in fiction.

A story or novel may and possibly should seem complete and rounded; it should tell a whole story or present a whole segment of a larger story. But this seeming completeness, if the fiction really works, is an illusion. The power is not necessarily, as Hemingway says, in what’s left out. But much of it flows from what a seemingly complete narrative leaves to implication.

I knew then that I wanted to write fiction again. I started The Fearless Man with the specific intent of showing what infantry combat in I Corps, Vietnam, 1967–1968, was really like. This time my canvas would be broader. I wanted to create a truthful and representative narrative. The eccentric, the aberrant, and the surrealistic had drawn other writers about Vietnam, but these had no appeal to me. I knew I was going after something elusive. My only hope was to stick to the story and to suppress any desire that might arise to “tell the truth.” I preached at myself to avoid preaching to my reader. My idea was this: let truth emerge; never tell it.

Once I may have stepped over this line, and Bob Loomis at Random House scolded me. I drew back.

I tried to be true to my characters, to write their stories, especially the stories of Mac and Paul, a combat leader and a chaplain, “torn” men in my sense of that word. They lived in my mind with sharper reality and deeper implication than any figure in a memoir ever could. Because of them I chose the truth of fiction over fact.

Excerpt from The Fearless Man

Mac advanced into the clearing on the hilltop—his new command post, he hoped—with a keen sense of being a stranger, and of danger.

He dropped to his right knee, propped his rifle against his side, looked over his shoulder, and crossed his wrists over his head. A fire team came forward and he sent them left to search the periphery of the hilltop. He repeated the signal and sent another fire team right. He brought up an eight-man squad, formed it in a wedge, and led it straight across the plateau.

It was a defensible position. He laid out a perimeter and the men of 1st Platoon began digging and setting out trip flares and claymore mines.

Walking the perimeter, Mac thought that the enemy could catch one of the squad-sized search teams down near the valley and fix it, and begin to kill marines. The squad would call for help and the platoon leader would charge into an ambush en route to the squad. The platoon would be fixed in its turn, and thus piece by piece Delta Company would rush into the fire.

Mac thought: “Every day we stay out here gives him more time to assemble his troops and figure out my pattern.”

But Mac would change his pattern with the gunny’s mission tonight.

“And maybe,” he thought, “the sky will clear and the planes will fly.”

And in some recess of his mind he knew there was another world where he would be changed from the creature that he was. He had forgotten how the change would happen. But if he could only stop for a minute, if he could only detach himself from this—from this—if he could only—