The following article is adapted from the forthcoming book '10 Excellent Reasons Not to Join the Military,' edited by Elizabeth Weill-Greenberg, published by New Press.

When Sergeant Jimmy Massey enlisted in the Marines, he never expected that he would be ordered to kill civilians. He enlisted in good faith, and he trusted his commander-in-chief to tell the truth, to follow the Geneva Conventions and the rule of law. He was even ready to risk his life for his country in the event that the United States faced a real or imminent attack.

In January 2003, Jimmy was deployed to Iraq. During the initial invasion he was involved in a number of "checkpoint killings," the kind of atrocities that occur over and over today without fanfare or scandal.

A hard-core Marine, Jimmy was in charge of a platoon of machine gunners and missile men. It was their job to secure the road out of Baghdad. As bombs rained down on the ancient city of 5 million people, civilians fled in panic. There was chaos at the checkpoints.

"All Iraqis," Jimmy told me in a recent interview, "were considered a menace.

"One particular incident really pushed me over the edge. It involved a car with Iraqi civilians. We fired some warning shots, but the car did not slow down. So we lit 'em up. Well, this particular vehicle we didn't destroy completely, and one gentleman on the ground looked up at me and said [in English], 'Why did you kill my brother? We didn't do anything wrong.' That hit me like a ton of bricks."

Jimmy was involved in four more checkpoint tragedies.

Like thousands of his fellow Marines and soldiers, who also enlisted in good faith, Jimmy was trapped between atrocity and near-sedition. If he followed orders, he might commit war crimes. If he disobeyed orders, he put his own life and career in jeopardy.

Marines are trained to kill without remorse. But there are times in life when indoctrination, reprisals, threats of humiliation, all fail to erase that inner feeling that we are all God's children. A Marine who recognizes the humanity of the people whose country is under occupation makes an ineffective killer. Repelled by the indiscriminate carnage, the visible suffering of the Iraqi people, who only deserved to be left alone by outside powers, Jimmy repudiated the war. He refused to participate in apparent war crimes. He defied authority, and his commander called him a coward and put him under a "kind of house arrest." Jimmy, a real fighter, eventually won his honorable discharge.

At his home in North Carolina, Jimmy says the U.S. military is committing war crimes. "Yes, I killed innocent people for my government. And for what? I feel like I've had a hand in some sort of evil lie at the hands of our government. I just feel embarrassed, ashamed about it. ... I spend long hours speechless and looking at the wall, seeing nothing but images of dead Iraqis."

Like Jimmy Massey, Darrell Anderson is fighting the dark ghosts of atrocity. A 22-year-old GI from Lexington, Kentucky, who won a purple heart after he was wounded, Anderson was stationed at a checkpoint near a police station in Baghdad, when a speeding car swerved in his direction. Darrell said he received orders to shoot. There was a family--two children, a man and his wife--in the car. Darrell's buddies screamed: "Shoot! Why don't you shoot? Why don't you shoot?"

According to Darrell, he simply could not pull the trigger of his M-16. "The car posed no threat," he told me.

"My superior came over and said, 'What are you doing?' I said, 'Look, there's children in the back. It's a family. I did the right thing. It's wrong to fire in this situation.' My superior told me: 'No, you did the wrong thing. You will fire, next time, or you will be punished. That's our orders.'"

There is constant pressure to kill Iraqi civilians, Anderson said. "At traffic stops we kill innocent people all the time. If you are fired on from the street, you are supposed to fire on everybody that is there. If I am in a market, I shoot people who are buying groceries."

The indiscriminate use of artillery is a direct violation of the Geneva Conventions, which state (Part IV, Article 48): combatants "shall at all times distinguish between the civilian population and combatants, between civilian objects and military objectives and, accordingly, shall direct their operations only against military objectives."

Darrell Anderson said he was riding in his self-propelled Howitzer when he was ordered to fire rounds into downtown Najaf in response to a mortar attack. Artillery rounds are filled with little BBs or shrapnel. Like cluster bombs, the "kill-ratio" is wide, and bystanders are covered in the blanket of destruction. Under orders, Darrell said, "we fired about 70 or 80 rounds. My buddies came back and said, 'We killed a lot of people.' About a hundred civilians. They were just people downtown. Killing downtown civilians is a typical incident."

Darrell was involved in numerous nighttime raids on Iraqi homes. "When we raid homes in the middle of the night," Darrell explains, "twenty guys blow through the house at gunpoint, and it's pretty terrifying for all the Iraqi families. We kick down the doors or bash them with a sledgehammer. One team goes in to clear the bottom floor. The second team heads upstairs. The women are screaming and crying, the children are freakin' out, and the men ask us, 'Why, why, what have we done?' We separate the women, and their men are handcuffed and taken away. Even if we are looking for a single person, all the men are considered enemy until proven otherwise."

Darrell compares Iraq to the tragedy of Vietnam, another American war in which unseen, distant commanders, whose own lives were never in danger, sent vulnerable young men and women into situations where war crimes become an everyday feature of military conduct. "Baghdad is in rubble," he said. "The big buildings were blown up. Many were targets, and houses in Najaf are blown to pieces."

Today Darrell is a war-resister. He left the military and escaped to Canada, where he is seeking political asylum. "I can't go back to the war. If I return to Iraq, I have no choice but to commit atrocities. And I don't want to kill innocent people."

War resisters today are challenging students to confront the issue of atrocity, to overcome denial, to consider the military, not as a career, or an opportunity, but as a way of life that claims and smothers souls.

War crimes in Iraq are not mere aberrations. They emanate from official policies regarding the aims and conduct of the occupation.

It is official policy, for example, to use cluster bombs in populated areas. Soldiers and Marines merely carry out the policy.

It was official policy, under Operation Iron Hammer, to put barbed wire around villages, to bulldoze crops, to bomb homes, and to hold families in jail until they released insurgent information (Patrick Cockburn, "U.S. Troops Bulldoze Crops," Counterpunch, Oct. 14, 2003). In his attempt to justify the punitive expedition, Captain Todd Brown, Company Commander of the 4th Infantry Division, stated, "You have to understand the Arab mind. The only thing they understand is force--force, pride, and saving face" (New York Times, Dec. 7, 2003).

It was official policy to level Fallujah, a city of 300,000 people, as an act of collective punishment. American commanders openly declared that Fallujah needed to be taught a lesson. Commanders ordered the use of 500-pound bombs that are utterly indiscriminate in their effects. No type of building--mosques, homes, medical facilities--was exempt from aerial destruction. At a mass burial of dead Iraqis, Captain P.J. Batty stated: "Everyone needs to understand there are consequences for not following the Iraqi government" (Associated Press, Nov. 16, 2004; also CNN, Nov. 16).

In her 2005 book, One Woman's Army, the Commanding General of Abu Ghraib, Janis Karpinski, exposes the connections between the use of torture at Guantanamo, in Afghanistan and Cell Blocks One and Two at Abu Ghraib. Major General Geoffrey Miller, Attorney General Alberto Gonzales, and Secretary of Defense Donald Rumsfeld played key roles in the preparation and execution of torture policy.

While Karpinski does not excuse the acts of reservists at Abu Ghraib, she reminds us that young Americans face prison time for following orders, while those who actually authorized the use of dogs, hooding, sleep deprivation, stress positions and isolation--techniques of torture--avoid accountability for the consequences of their own decisions. During the Abu Ghraib scandal, neither Rumsfeld, Miller, Gonzales--not one top official or commander --stepped forward to share responsibility with the reservists. In essence, Karpinski makes clear, American commanders left their soldiers in the lurch.

Every American youth who considers military enlistment needs to take a close look at military "justice."

Not only are American Marines, reservists, and soldiers expected to follow unlawful orders, they are also expected to bear life-long burdens of shame, guilt, and legal culpability for the arrogance of their own commanders--who dispense life and death from an office computer. Even before the invasion of Iraq in April 2003, more than 600 U.S. veterans signed a "Call to Conscience," expressing remorse for past war crimes. "As troops," they wrote, "in the last Gulf War we were ordered to murder from a safe distance. We remember the road to Basra where we were ordered to kill fleeing Iraqis. We bulldozed trenches, burying people alive."

Once a student makes that fateful decision to enlist in the U.S. military today--once an individual, through basic training, is conditioned to kill without remorse, to become an occupier in a country where insurgents are indistinguishable from neighbors, friends, and family in their own homeland--it is too late to turn back. As war historian Gwen Dyer writes: "Men will kill under compulsion--men will do almost anything if they know it is expected of them and they are under strong social pressure to comply."

"Only exceptional people can resist atrocity," writes psychiatrist Robert Lifton in Superpower Syndrome. Jimmy Massey, Darrell Anderson, Aidan Delgado and scores of other war-resisters are exceptional men and women. When they enlisted, they only wanted to serve their country. They hoped to make a difference. But the military transported them beyond the rule of law, turning them into occupiers of Iraq, not defenders of democracy. These war-resisters fought back and broke the military code of silence.

Americans can hold on to their humanity, to be sure. But only by recognizing the humanity, not only of Arab peoples, but of all peoples who have a right to self-determination like ourselves.

Refusing to enlist is more than a career decision. It is a moral and political act, a contribution to the burgeoning, international movement for a better, more peaceful world. It is an affirmation of the sacredness of life and the dignity of all humanity.

Paul Rockwell, formerly assistant professor of philosophy at Midwestern State University in Texas, is a writer in the Bay Area and a columnist for In Motion magazine and Common Dreams website. He appears at a reading with Anthony Arnove on Tuesday, May 2, at 7:30pm at the Capitola Book Café, 1475 41st Ave., Capitola; 831.362.4415.

Send a letter to the editor about this story.