Lieutenant William Calley was the only person convicted of any crime after the My Lai massacre in Vietnam. He served three and a half years under house arrest after President Richard Nixon intervened to keep him out of prison.Associated Press

“We fight with the values that we represent; we don’t adopt those of our enemy.” This is what I told the marines standing in a loose semicircle around me on our forward operating base outside Karmah, Iraq, one day in December 2008. “If we lose sight of that, we’ve got nothing left.” I meant every word. For many of us, making sense of the war in Iraq was becoming harder, but we needed to believe that we were fighting for something. Most could articulate a version of that argument themselves during squad-level discussions back in Hawaii, but now it was hard to tell what impact my words were having. I watched the familiar faces as I spoke. Some nodded, others looked at the ground, shifting their feet on the gravel or gazing back impassively, their expressions a reflection of the gray skies and drizzling rain.

The day before, the same faces had watched, blanched with shock, as the battalion sergeant major and I removed the remains of the 19-year-old Thomas J. Reilly from the Humvee in which he had died. In a war in which death was customarily delivered remotely by roadside bombs, T.J.’s killing had been an unusually personal one. As his Humvee passed through Karmah’s darkened streets, someone standing just feet away threw an RKG-3 anti-tank grenade—an unusually sophisticated weapon for that war—sending a shaped charge of molten steel through the roof of the vehicle, killing T.J. and wounding the other three members of his fire team. I was nearby when the incident happened and arrived on the scene within minutes. One look at the faces around the wrecked Humvee told me that what lay inside would be bad. It was. That image remained in my memory, the way the shadow of an object seen in the bright sun lingers on your retina when you close your eyes.

To almost everyone in Charlie Company, T.J. had been a familiar figure—an irrepressibly good-humored marine well liked by his platoon-mates, most of whom had been together since boot camp. From London, Kentucky, he had been brought up by his mother, Georgina, to whom he was dutiful in a way that few teenagers are. He called and wrote regularly, trying to reassure her that things weren’t as bad in Iraq as the news made it appear. His hobby was cooking. Impervious to the ribbing it inspired from his squad-mates, he had plans after the Marine Corps to become a chef. Now he was on his way back to his mother in a casket marked “remains unviewable,” and we were leaving on an operation to find his killers. A “cordon and search,” I called it—but it was really to get Charlie Company back on the streets, giving them the catharsis of purposeful action, rather than leaving them sitting on base to brood.

I harbored little hope of finding clues that might lead us to the men who had killed T.J. The city of Karmah was a dark place, its sullen population and unlit streets redolent with menace. A succession of Marine battalions had been badly mauled there over the years with little to show in return. The commander of the battalion that had preceded us, a close friend of mine, had died in a suicide-bomb attack days before our turnover. His unit, which had poured hundreds of thousands of dollars into various projects around the city, left angry and bitter, convinced that a prominent local sheikh, a recipient of much U.S. largesse, was behind the attack.

I was aware that the marines of Charlie Company would want revenge for T.J.’s death—and among young men trained for violent confrontation, such a desire can find explosive outlet unless resolutely curbed. Your moral resolve sags under the experience of combat in a place like Iraq: fatigue from lack of sleep and the enervating effort of lugging body armor, weapons, and equipment in breathless heat; persistent exposure to a culture in which, at least to our eyes, the locals seemed to show casual cruelty to others of different tribes and denominations, and that, to us, appeared to exalt brutality; and the frontal-lobe numbing effect of fear, grief, and white-hot anger. I had experienced that anger myself—despite having two decades on my marines, and degrees in philosophy and law—and I wasn’t foolish enough to assume that my talk to them that morning would make a difference.

Nevertheless, I wasn’t concerned. I knew that the leaders closer to them than myself, their sergeants and lieutenants—though still reeling from the loss themselves—would restrain their subordinates from venting their anger on the local population. That may sound like reckless faith, but we had prepared for moments like this, and I knew that I could trust them. And all of us understood the consequences of failing to do the right thing—for our unit, for our cause, and for ourselves.

Memories of Karmah came back to me three weeks ago, when President Donald Trump granted a pardon to Michael Behenna, a former Army lieutenant convicted of the murder of an Iraqi prisoner in 2008.

“We know we have a president who is very sympathetic to the very difficult situation that soldiers, sailors, and marines were put in during the Iraq and Afghanistan wars,” John Richter, the lawyer who defended Behenna in court, told The Washington Post. Since then, The New York Times and others have reported that, around Memorial Day, the president intends to pardon other servicemen accused or convicted of war crimes. Among the names that have been floated are Naval Special Warfare Operator Chief Eddie Gallagher and Green Beret Major Mathew Golsteyn, both of whom have been charged with murder and are pending trial. Golsteyn stands accused of murdering a detainee, while Gallagher faces allegations that he shot civilians and stabbed a prisoner to death. The president’s comments came against a backdrop of sympathetic media coverage of both men, and amid appeals by politicians on their behalf.

Behenna, Golsteyn, and Gallagher held leadership positions within elite units and were all described in the media as being highly decorated heroes. The public seems uneasy to see such Americans in the dock.

They are men of proven character, runs the subtext. If they did lose their way, it was because of what they went through, because of what they did for their country. And when you’re fighting a vicious enemy, sometimes the rules just don’t make sense. It’s a superficially beguiling message, but one that undermines rather than supports the sacrifice of those who serve. As a combat veteran myself, I watch these developments with deep unease.

If the men in question had been junior soldiers, I might feel differently. But when the military gives you responsibility, it comes with the understanding that you can’t abandon it by blaming the stressors of combat. Because it’s in combat when your subordinates depend on you the most—when fear, fatigue, and anger threaten to take them off path, and when, lacking firm guidance, they are likely to blunder down a dangerous path. Among the squad leaders whom I sent into Karmah that day were a number who had earlier served with me as junior marines in the Battle of Fallujah, during a four-month period in which the same battalion had seen 45 marines killed, with another 250 wounded. None of them used that fact as an excuse to abuse prisoners or the local population—then or afterward. That doing so was forbidden was just understood.

Just over 40 years before I addressed my marines in Karmah, another Charlie Company reacted very differently to the impact of fear and loss. On March 16, 1968, in the Vietnamese village of My Lai, U.S. soldiers killed between 347 and 504 unarmed Vietnamese civilians and raped approximately 20 women and girls, some as young as 10 years old. In an article published in The New York Times on the 50th anniversary of the incident, Christopher J. Levesque illustrated that until that point, there was nothing remarkable about Company C, 1st Battalion 20th Infantry. Demographically, the soldiers who composed the company were an average representation of the U.S. Army, even slightly better educated than the norm in terms of high-school-graduation rates. They came from homes across America, cities and small towns and remote rural areas.

And what emerged in subsequent media interviews with these young soldiers was their absolute ordinariness.The only thing exceptional about them was their leadership, or rather, its absence. Charlie Company’s commander, Captain Ernest Medina, was a singularly unpleasant individual who, according to subsequent testimony, was in the habit of beating detainees during interrogation. The platoon that did most of the killing was headed by Second Lieutenant William Calley, who reportedly killed an unarmed farmer in front of the platoon several days before the massacre. Calley was the only person convicted of any crime, serving three and a half years under house arrest after President Richard Nixon intervened to keep him out of prison.

When I was a lieutenant at the Basic School for Marine officers, the story of the My Lai massacre was required reading, and the lesson was clear: Nothing absolves a leader from upholding the law of war. That lesson may now appear blurred by the passage of time and the implicit belief that such a thing couldn’t possibly happen again. Today’s all-volunteer force may be better educated than its draftee predecessor, but the alchemy of combat without firm direction remains as morally destructive as ever.

In 2006, in the Iraqi town of Mahmudiya, a group of soldiers from the 101st Airborne Division gang-raped a 14-year-old Iraqi girl before killing her, her 6-year-old sister, and both her parents. It’s a story made all the more shocking because these weren’t reluctant draftees but well-trained volunteers belonging to a storied unit with proud traditions. In Black Hearts: One Platoon’s Descent Into Madness in Iraq’s Triangle of Death, the author Jim Frederick recounts the story of how 1st Platoon, Bravo Company slid into a state of collective sociopathy. In the book’s foreword, Frederick notes a marked contrast in behavior between 1st Platoon and its two sister platoons within the same company, “who labored under exactly the same conditions but who had come home with far fewer losses and their sense of brotherhood and accomplishments more or less intact.” The difference, Frederick concludes, was leadership: The other two platoon commanders were uncompromising when it came to adherence to the rules of war.

In November 2005, after losing one of their comrades to an IED, a squad of marines was involved in the unlawful killing of 24 Iraqi civilians in the town of Haditha. When the news broke, I overheard my boss, a Marine colonel, assure his wife, “Well, of course they didn’t do it.” Part of me envied his cheerful naïveté, but I had witnessed firsthand the corrosive effect that sustained exposure to violence and fear can have on previously held moral convictions. I knew that under the right circumstances, almost anyone is capable of committing a war crime. Those circumstances had come together for me on a fire-swept street in Fallujah, when I found myself balling my fists as two detainees were led past the bodies of the two marines whom I had just seen them kill. I wanted those Iraqis dead. I learned then firsthand how combat can make good people do bad things, which is exactly why it’s so important to reinforce the message that it’s not okay to do so.

In the aftermath of Haditha, the commander of the unit involved was relieved of his duties. A year later, I listened with a group of fellow battalion commanders as then–Lieutenant General James Mattis explained to us why he had made that decision. “As a leader, you can’t be a gray man,” Mattis said. “Those of you who are introverts need to change or find another profession, because if you aren’t aggressive about establishing ethical standards, someone else will fill that vacuum. Our Marine hymn reminds us to keep our honor clean. And the consequences of failing to do so, for our cause and for the young men and women involved, will be profound and irreversible.” It might never have occurred to Mattis to remind us that leaders themselves shouldn’t commit war crimes; surely they knew.

I wrote his words down at the time, and in the years since have been reminded often of their truth. When a leader, through his actions or inaction, grants his subordinates unrestricted license to kill, he neglects his responsibility for their welfare and undermines the cause for which they are risking their lives. Moral injury can be every bit as disabling as physical or other, psychological wounds.

And the “all’s fair in war” argument backfires when a civilian population seeks revenge against an occupying army that treats it with ruthless disdain. Being subjected to brutality tends to strengthen a person’s resolve and nurture a desire for revenge. The killings of civilians in Mahmudiya and Haditha were widely covered by the Arab media and became a rallying cry for our enemies.

It’s now been more than a decade since Lance Corporal T.J. Reilly was killed in Iraq. I think about him often, and the many others I have known who fought honorably and died for their country. Memorial Day is meant to be the day when America honors their sacrifice—not an opportunity to excuse those whose actions sully the cause for which they died.

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