For years, I’ve argued that PTSD is really two very different disorders, improperly lumped together as one by the American Psychiatric Association in its Diagnostic and Statistical Manual of Mental Disorders (DSM).

The first, of course, is the fear of being killed which manifests itself in hypervigilance, vivid nightmares and flashbacks. It’s about what others have tried to do to you.

But the second, which I’ve come to call the Wounded Soul Syndrome, is based in the guilt of what you have done to others. It’s about violating your own moral code, about trying to reconcile your actions to your beliefs.

I saw a classic example of the Wounded Soul Syndrome recently in a guest column published in the Washington Post. Authored by retired Marine Capt. Timothy Kudo, it said that military suicides reflect the moral conflicts of war.

“I held two seemingly contradictory beliefs: Killing is always wrong, but in war, it is necessary. How could something be both immoral and necessary? I didn’t have time to resolve this question before deploying,” wrote Kudo, who had deployed to Iraq in 2009 and to Afghanistan in 2010-11. “And in the first few months, I fell right into killing without thinking twice. We were simply too busy to worry about the morality of what we were doing. But one day on patrol in Afghanistan in 2010, my patrol got into a firefight and ended up killing two people on a motorcycle we thought were about to attack us. They ignored or didn’t understand our warnings to stop, and according to the military’s ‘escalation of force’ guidelines, we were authorized to shoot them in self-defense. Although we thought they were armed, they turned out to be civilians. One looked no older than 16.”

Kudo, who’s now a graduate student at New York University, says he thinks about killing those people on the motorcycle every day. He also remembers the first time a Marine several miles away asked him over the radio whether his unit could kill someone burying a bomb. The decision fell on him alone, and he said yes.

“Many veterans are unable to reconcile such actions in war with the biblical commandment ‘Thou shalt not kill.’ When they come home from an environment where killing is not only accepted but is a metric of success, the transition to one where killing is wrong can be incomprehensible,” Kudo wrote. “This incongruity can have devastating effects. After more than 10 years of war, the military lost more active-duty members last year to suicide than to enemy fire. More worrisome, the Department of Veterans Affairs estimates that one in five Americans who commit suicide is a veteran, despite the fact that veterans make up just 13 percent of the population.

“While I don’t know why individual veterans resort to suicide, I can say that the ethical damage of war may be worse than the physical injuries we sustain. To properly wage war, you have to recalibrate your moral compass. Once you return from the battlefield, it is difficult or impossible to repair it.”

Kudo says he didn’t return from Afghanistan as the same person – “I’m no longer the ‘good’ person I once thought I was.” He says he wrestles with justifying his actions, but that he’s beginning to believe that killing, even in war, is wrong.

I have to salute Kudo’s courage and honesty in writing this Op-Ed piece. It should make us all reconsider what we’re asking our young men and young women to do in combat.