Fighting effectively without committing war crimes

and mistreatment morally wrong, they served as a billboard for enemy recruiting efforts, French said. When dehumanization occurs on both sides of a conflict, it can lead to cycles of escalating atrocities.

Even if they do not participate in an atrocity, troops who generate intense disgust and contempt to help them kill will have a harder time readjusting to civilian life after the violence is over, French said. “It is important for our troops to know that they have fought honorably. But there is no honor in killing subhumans. Those who encourage dehumanization of the enemy are not really acting in the troops’ best interest.”

The release notes that training troops to objectify with language such as  “neutralizing threats” and “taking down targets” is less damaging, the researchers contend.

This is not to say that objectifying in order to kill is a free pass to a clear conscience. “We believe only psychopaths can permanently avoid re-examination of their actions from an empathetic perspective,” Jack said. ”Objectifying is a necessary but temporary fix. To feel fully human ourselves, we need to be able to reconcile our actions towards our fellow humans. That is easier to achieve if you have objectified in a limited way for a good reason, although it often still requires some readjustment and sorrow. The situation is much harder psychologically if you have descended into hatred and contempt.”

Post-conflict reconciliation is vital to veterans.  As a recent National Public Radio story reported, even drone pilots, who face no personal danger, often suffer from PTSD and can struggle with reconciling the deaths they caused or viewed through cameras from thousands of miles away.

A core principle in military ethics is that it matters who you kill, and why. Killing can be reconciled as an honorable act of defending against a real threat, whether to one’s own life or to the lives of others you are defending, French said. “This warriors’ code is what protects our troops from crossing the line from warrior to murderer and sacrificing their own humanity.”

Jack said more research is needed, but this work suggests they can develop psychological tests to check that troops are battle-ready. “Before we ask them to fight for us in battle,” he said, “we need to be sure our troops are ready to switch between the two major networks in the brain just as you and I can do in our much gentler civilian lives.”