"I JUST WANTED the college money; that's all I wanted," says John Milton, shaking his head. "But I never went."

Like many Americans, he was lured into the pre-9/11 Army for the money, and, honestly, for the adventure.

He got more than he bargained for in the post-9/11 Army when he was sent to Kuwait, where it was safe, then volunteered for Iraq, where it was not.

A tall, burly man who makes his living in the building trades, Milton says his grandfather, a Korean War vet, had warned him to never volunteer, but Milton was young, and every generation has to learn hard lessons for itself.

Milton's hard lesson, in addition to his occasional nightmares and daily guilt, is knowing he could be prosecuted as a war criminal.

There is no statute of limitations on war crimes, according to Syracuse University law professor David M. Crane, a former war-crime prosecutor, and others I asked.

That's why, in exchange for his true story, I have given the Iraq veteran a false name and have omitted some personal details. Everything included is accurate.

Much of his time in the Army, Milton was a medic, but not a noncombatant. "Everyone's an infantryman first; that's what you learn in basic training," he says. He never wore a helmet with a red cross on a white field because "It's like a big, red bull's eye," says Milton. Medics can be identified by the 50-pound bag of medical supplies they carry, plus a rifle and a sidearm. Milton's pistol was a 9 mm Beretta.

He committed a war crime with the Beretta.

In 2003, attached to the Third Infantry Division, he and five buddies were returning from a beer run into town from their base - buying Jordanian Horse Head beer from an Iraqi entrepreneur who served hot grilled chicken in the front of his stand and warm beer in the back. They were riding in two Humvees when a roadside bomb blasted the passenger side of the vehicle Milton was driving. Before the smoke cleared, a shocked Milton looked down and saw his buddy's eyeball in his lap.

Milton and the soldier in the back seat were not injured, nor were the GIs in the second vehicle, who saw the man who planted the bomb and shot him several times. He was down, but not mortally wounded.

The soldiers were screaming, punching and kicking him. Like his buddies, "I was a little crazy," Milton says. Instead of medicating the insurgent, he drew his Beretta and shot him in the head, killing him.

Milton didn't regret it then, but he does now.

He was not yet 21, likely in shock, trained by the Army to kill. Had he fired that same bullet into the Iraqi one minute earlier, when he was vertical, it would have been OK. But because the Iraqi was horizontal, it was not.

That was the worst thing he did. He tells his story for the first time not to seek forgiveness, but to explain to the 99 percent of Americans who do not serve what happens to the 1 percent who do. Milton is a surrogate for the hundreds of thousands of Americans we send to war in hostile lands against an enemy that attacks wearing no uniform.

This is another story:

At the wheel of a Humvee driving into Iraq, "The locals were happy to see us. Kids, they're running wild all over the road, and a little kid ran right in front of me," and he felt the sickening thump of his wheels passing over the child.

"Being a medic, I wanted to stop and help. I said, 'Dude, what do we do? Should I stop?' "

His passenger said no, maybe for their own safety.

"We kept going and left him at the side of the road," says Milton, his voice trailing off. "I felt awful just leaving him there. He's a 4-year-old kid. I guess he was just happy to see us."

It was an accident, I say.

"It was, but it's something I deal with every day, especially when I'm driving." He takes a breath and clears his throat.

"Every day, everything I've told you runs through my mind."

This is all eating him up, and he did not come to me willingly.

Following a column I did on the Marines who urinated on Taliban corpses, Milton wrote me, saying everyone should calm down, that he and others had done worse. After several conversations he agreed to tell me his story, in order to put things into perspective.

We had a long talk in his neat house in New Jersey, not far from Philadelphia and not far from the Delaware.

Milton's life is peaceful, but his mind is not. He went to a VA hospital and spoke to a psychiatrist, but found no relief from his demons of grief and guilt. He was prescribed drugs, but "they made me feel dead," so he stopped taking them.

The shrink "didn't understand what I was talking about," Milton says, frustrated. "He said it's OK to feel that way, but he couldn't tell me how to stop feeling that way." Milton is wounded.

Before the Army, "I used to love being around people, but no more." Now he's thinking about moving to someplace like Montana or Wyoming where it is vast and quiet and empty.

During his military career, there were other infractions, never reported to officers because "sometimes the orders came from the officers," Milton says.

While working on a seriously wounded enemy soldier, he was told by an officer to "help him along," meaning euthanize him. Milton did so without qualms early on. "I'm 20 years old and I'm sent over there with a badass attitude. I didn't care."

The more he did it - five, six, seven times - the less he liked it. As his conscience emerged, he eventually refused to do it. "I can still see every one of their faces, individually, exactly what they looked like that day."

Since a prisoner is a "protected person," explains law professor Crane, allowing him to die "could be construed as a war crime."

The defendant, under the Uniform Code of Military Justice, would be charged "with the substantive crime," in this case, a degree of homicide.

Before entering Iraq, Milton remembers being lined up on the border and watching Scud and American missiles crossing overhead.

"It was like watching a fireworks show. It didn't affect me in any way. Wow!" he thought, "It's kind of cool."

He didn't feel much fear, not even the first time he got shot at. "I guess they prepare you well. It felt like a big training exercise."

The next morning, however, he awoke with "a lot less hair and cold sores in my mouth. The stress got to me," he says.

The stress wasn't constant, but it was heightened outside the camp's perimeter.

Inside the perimeter, there was abuse of prisoners. If they didn't respond fast enough to orders, a rifle butt to the head sped them up.

"Some of these combatants didn't want to be treated well," Milton says. "They'd s--- in the bidets and want us to clean it up."

One "high value" captive spit in Milton's eye and the MPs guarding him turned their backs so Milton could give the wounded prisoner "an ass-whipping." That was not hate, just an object lesson.

"They tell you it's wrong to do this, it's wrong to do that, but what are they training us to do?" Milton asks. "You know what I mean? When you go to basic training, everything is kill, kill, kill."

Milton says he respects Iraqis, even the " bad people."

The insurgents "totally, 100 percent believe in what they're fighting for. They do not give up. I'm not saying they are right. I'm not saying that at all, but you've got to give them credit."

John Milton never got to college, but he did get an education.