The Military Ethicist’s Role in Preventing and Treating Combat-related, Perpetration-Induced Psychological Trauma


Major Peter G. Kilner

Infantry, U.S. Army



DRAFT, 3 January 2005


Abstract: I argue that military ethicists have an important role to play in preventing and treating combat-related Perpetration-Induced Traumatic Syndrom (PITS), which is a particular form of Post-Traumatic Stress Disorder (PTSD).   Recent research provides compelling evidence that guilt resulting from having killed in combat is a very significant factor in a veteran’s development of PITS/PTSD.  However, the military’s medical community is not addressing this factor.  This is not surprising, given that the medical community as a whole tends to focus on environmental conditions and what happens to a person, not on what a person does.  Ethicists, in contrast, do focus on people’s actions and on the morality and repercussions of their actions.  I propose that military ethicists take a leading role in generating an organizational dialogue on the morality of killing in order to prevent and treat psychological trauma that is caused by the guilt of having killed in combat and not being able to make sense of the experience.



Five years ago at this conference and two years ago in Military Review[1], I argued that military leaders have an obligation to explain to their soldiers the moral justification for killing in combat. The argument was: since we recruit soldiers to kill, train them to kill, develop plans for them to kill, and order them to kill, we also owe it to them to explain why killing in war is morally justified, because we don’t do this, and there is a lot of evidence that many soldiers cannot live with having killed.  At the time, my evidence was qualitative and largely anecdotal. Although research at the time did indicate overwhelmingly that combat exposure and participation in atrocities predicted PTSD, the interpretation of this evidence focused on what had happened to the soldiers (e.g., experienced fear, witnessed dead bodies), not on what the soldiers had done (i.e., killed).


I. Killing in combat can lead to PITS/PTSD

Led by the seminal work of Rachel MacNair[2], there is now a growing body of research that indicates that what soldiers do—not only what happens to them—can lead to psychological trauma.  Using data from the National Vietnam Veterans Readjustment Study (NVVRS), MacNair compared veterans who reported that they had killed in Vietnam to those who reported that they had not killed.  She discovered that those who had killed in combat scored higher on most indicators of PTSD, as measured by the Minnesota Multiphasic Personality Inventory (MMPI).  The NVRRS data indicated that veterans who had been directly involved in atrocities were much more likely to report symptoms of PTSD than were veterans who merely witnessed atrocities.[3]  Also, while combat exposure and PTSD are correlated, veterans who reported that they had killed during an overall tour of light combat were more likely to show PTSD symptoms than were those who reported that they had not killed during a tour characterized by heavy exposure to combat.[4]  In other words, killing—much more so than exposure to atrocities or combat—is a major factor leading to PTSD. 


The symptoms of those who have killed in combat—as part of an atrocity or legitimate activity—are significantly different from those who have not killed.  MacNair found that those who reported they had killed were much more likely to report having done something in the military that they will never tell, to have violent outbursts, to have intrusive nightmares, and to abuse alcohol.[5]


A review of the literature finds other studies that support a link between killing in combat, guilt, and PTSD among Vietnam veterans. Breslau and Davis (1987) found that the experience of participation in atrocities increased by 42% the probability that a veteran would be diagnosed with PTSD, even when the number of combat stressors was controlled. Vargolias (1997) found that combat and atrocity exposure predicted guilt and PTSD.  Nelson-Pechota (2003) found that alienation from God and difficulty reconciling one’s faith with Vietnam experiences were related to higher levels of guilt and PTSD symptomology, and that religious worship is a mediator between combat severity and affective guilt. 


II. The Army is addressing PTSD, but not killing as one of PTSD’s main causal factors.

American Soldiers and Marines are doing a lot of killing in the Global War on Terror, so we should not be surprised that an Army study found that almost 17% of Iraq veterans and 11% of Afghanistan veterans reported symptoms of major depression, severe anxiety, or PTSD soon after returning from their combat deployments.[6]  Those numbers will likely increase as soldiers experience multiple combat deployments.  Moreover, there is evidence that veterans who show little sign of PTSD over their working lives start showing signs of it at retirement.


The Army medical community “is trying to take a proactive approach to mental health,”[7] said Dr. Charles W. Hoge, chief of the department of psychiatry and behavioral sciences at the Walter Reed Army Institute of Research.  Deploying soldiers are given pre- and post-deployment health questionnaires, and 7 of the 17 questions seek signs of depression, anxiety and PTSD.[8]  The problem is, the post-deployment questionnaire asks only what happened to the soldiers (e.g., Did you see a dead body?), not whether they killed someone. 


A recent New York Times article that quoted military psychologists extensively reported:


Psychiatrists say the kind of fighting seen in the recent retaking of Falluja—spooky urban settings with unlimited hiding places; the impossibility of telling Iraqi friend from Iraqi foe; the knowledge that every stretch of road may conceal an explosive device—is tailored to produce the adrenaline-gone-haywire reactions that leave lasting emotional scars.[9]


This and every other statement I have seen in media reports indicate that the military medical community is still looking at the PTSD problem exclusively from the perspective of what soldiers endure, not what they do. In contrast, these words of a battalion chaplain in Iraq express well the concerns of soldiers.


Capt. Tim Wilson, an Army chaplain serving outside Mosul, said he counseled 8 to 10 soldiers a week for combat stress…”There are usually two things they are dealing with,” said Captain Wilson, a Southern Baptist from South Carolina.  “Either being shot at and not wanting to get shot at again, or after shooting someone, asking, ‘Did I commit murder?’ or “Is God going to forgive me?’ or ‘How am I going to be when I get home?’”[10]


How is it that the medical community can study the psychological trauma of soldiers in combat yet not pay attention to whether they have killed anyone?  After all, as one OIF-vet lieutenant said in a PlatoonLeader forum discussion on the psychological impact of killing, “Frankly, anyone who says that they are perfectly fine after killing another human would scare the hell out of me.”  McNair offers an explanation for this blind spot.  She argues that sympathy for soldiers has made researchers and others unwilling to “blame the victim.”  It is much more pleasant to believe that PTSD results from what an unknown enemy did, not what your nation’s soldier did.[11]  


Even if the psychiatric profession did decide to address soldiers’ guilt about killing in war, there are doubts about its ability to effectively engage the problem.  Mental health professionals tend to treat guilt as a symptom of a condition to be treated, not as a healthy moral response to a perceived moral transgression.  Psychologist James Story put it this way:

The guilt of combat veterans resulting from acts of commission during wartime has been associated with chronic and persistent life problems. Traditional psychological treatments that respond to guilt primarily as a symptom are not well suited for the profound existential issues faced by veterans who acknowledge, or attempt to acknowledge, that their acts have caused great harm to others.[12] 


Research indicates that therapists become less sympathetic to and have difficulty listening to patients with PTSD who talk about killing.[13]  That is not surprising; mental health professionals and combat soldiers live in different worlds.  Several officers in Iraq have told me that they and their soldiers do not talk with the Combat Stress Teams who sometimes arrive after battle, because “they don’t understand.”


 In a sense, then, veterans themselves must bear some of the blame for the lack of understanding about combat-related psychological trauma.  Due to fear of judgment by non-veterans who “don’t understand” and might judge them harshly, they do not express their experiences.  This only perpetuates the problem, as veterans keep silent about their symptoms so as not to appear crazy, which in turn makes those with symptoms feel crazy and alone because no one else seems to have their symptoms.[14]  


III. What to do?  Break the Taboo

It makes sense that the veterans in the NVVRS who killed in combat were more likely to report both that they did things in the military that they will not talk about and that they are more likely to suffer from intrusive dreams.  Perhaps they are suffering from nightmares precisely because they feel unable to talk about things they did, like kill another human being.[15]


As long as there is war, there will be killing.  The solution to preventing and treating perpetration-induced trauma, then, lies in enabling soldiers to deal with having killed. As LTC (ret) Dave Grossman put it, “You are only as sick as your secrets.”[16]  We must end the taboo on talking about killing and the troubling feelings that killing gives rise to.


We must help our brothers and sisters in the military to understand that feelings of guilt about killing in combat are more likely a sign of moral strength than of mental weakness.  The current practice of having re-deploying units identify “high-risk soldiers” to receive counseling sends a terrible message. In one Army study, more than half of the soldiers who met criteria for PTSD reported that they had not sought help due to fear they would be stigmatized and held back in their career.[17] It’s no wonder that redeploying soldiers have shown an “abysmal” level of candor in screening.   “We still have a long way to go,” admitted one Pentagon medical officer.  “The warrior ethos is that they are no imperfections.”[18]


One way to break the taboo is to speak publicly about how feelings of guilt associated with killing in combat are normal, healthy, common, and not indicators of moral culpability.  There is such thing as misguided guilt. For example, someone who is driving a car, under the speed limit and paying attention, who happens to fatally hit a child who darts out into the road, will likely feel terrible guilt.  He or she will have participated directly in the death of another person, even though he did nothing morally wrong. So it is with justified killing in war.  Soldiers need to hear the message that feelings of guilt are not necessarily tied to doing anything morally wrong and are normal in a healthy person.


McNair finds that veterans respond very positively to her talking about the normal feelings of guilt for killing.

They are grateful, because the conclusion they draw is that they are in fact having a normal response, that symptoms they had not told others for fear of appearing crazy were in fact typical and prevalent responses to the circumstances they had undergone.  Even if their symptoms were mild enough that they did not seek therapy and could not be said to have a disorder, it was a relief for them to have the knowledge of natural, explainable, common psychological consequence.[19]


A second way to prevent and treat PTSD is to enable those who have killed to talk about their experiences with those who understand.  Grossman contends that


[P]ain shared is pain divided.  And the mean by which this ‘sharing’ can occur is in a group critical incident debriefing, shortly after the trauma, in which each individual completely works through what occurred and receives the acceptance, forgiveness and support of  their fellow victims.


I asked an infantry company commander in Iraq what his soldiers needed most from him in combat. “After a fight they need me to pat them on the back and tell them they did the right thing,” he said.  “They just need that assurance.”  His response happened in the context of an interview on tactical issues, not one about morality.


Veterans Administration psychiatrist Jonathan Shay explains the value of this sort of conversation by saying that “narrative can transform involuntary reexperiencing of traumatic events into memory of the events, thereby reestablishing authority over memory.”


Conversation also develops relationships.  Research shows that Vietnam veterans with PTSD report lower levels of social support (Keane et al, 1985).  This month, I plan to establish a private online discussion community for officers who have killed in combat and want to talk about their experiences with others like them. This will give them an opportunity to talk honestly about their experiences and to develop a support group. I should have initial results by the time of JSCOPE 05. 



The psychological well being of our combat veterans requires a cultural shift within the armed forces.  They need a military that recognizes what they know all too well—that killing, even justified killing, exacts a psychological toll.  As military ethicists, we are best able to start and lead dialogues—in our services, our units, one-on-one—that replace the taboo on killing-related trauma with an honest conversation about it.



[1] Peter G. Kilner,  “Military Leaders’ Obligation to Justify Killing in War,” Military Review, vol 72, no 2, Mar-Apr 2004, pp. 24-31.

[2] Rachel M. MacNair, Perpetration-Induced Traumatic Stress: The Pshychological Consequences of Killing, Westport, CT: Praeger, 2002; and, Symptom pattern differences for Perpetration-Indcued Traumatic Stress in veterans: Probing the National Vietnam Veterans Readjustment Study. Doctoral Dissertation, University of Kansas, MI, 1999.

[3] See also Jack A. Schapiro, Trait dissociation among Vietnam veterans with combat-related posttraumatic stress disorder.  Doctoral Dissertation, Pepperdine University, 1999.

[4] MacNair, Perpetration, 174.

[5] Ibid., 18, 178.

[6] Anahad O’Connor, “1 in 6 Iraq Veterans Is Found to Suffer Stress-Related Disorder,” New York Times, July 1, 2004.

[7] Ibid.

[8] Scott Shane, “A Flood of Troubled Soldiers Is in the Offing, Experts Predict,” New York Times, December 16, 2004.

[9] Ibid.

[10] Ibid.

[11] MacNair, Perpetration, 162.

[12] James E. Story, Therapist countertransference where combat-related guilt is a central factor involved in psychological treatment of combat veterans, Doctoral Dissertation, University of New Mexico, 1997.

[13] MacNair, 91.

[14] Ibid., 163.

[15] Ibid.

[16] Dave Grossman, 

[17] Shane.

[18] O’Connor.

[19] MacNair, 165.