A friend of mine, a nurse, lives on a dangerous S-curve and has run to help with over 100 accidents, more than a few fatal, in the past 20 years. She recently sat by a baby whose heart was still beating but who died soon after. The scene replays itself repeatedly in her mind as she wonders if she might have done something differently to save the girl's life.

She copes by calling the Ohio Department of Transportation, begging that blinking lights and warning words be put on the road to prevent further death; by praying for the mother/driver and going with her to visit the baby's grave; and by reviewing her first aid skills and keeping gloves and other supplies on hand.

About the same time as the accident, I read of a Marine who helped remove bodies of dead Iraqi civilians from a house where some of his fellow Marines had gone on a rampage. He picked up a young girl and some of her brains dripped on his boot. The news report said that he is receiving intensive counseling, unable to deal with the experience.

I have talked to people with post-traumatic stress disorder, which about 1 in 8 returning Iraq combat personnel have. We don't have statistics for 10 years after duty in this current war, which is when most Vietnam vets were diagnosed. However, eventually, about 30 percent of people who spend time in war zones (not just the combatants, but also the civilians) experience PTSD, and up to an additional 25 percent have partial PTSD.

I've seen how PTSD robs these folks of their ability to live productive lives, to maintain relationships, to get a full night of sleep. When in a room, they must sit facing the door, they have trouble focusing on the conversation, experience memory loss, and their bodies move constantly from nervousness.

Perhaps God's commandment to not kill comes from a knowledge none of the rest of us can claim. God created the human psyche, which appears about half the time unable to handle the horrors of war, of mutilated bodies. Sadly, some horrors seem unavoidable, as in car accidents, but others can be avoided, as in a decision to use violence to resolve conflict. It seems humans just can't have a good war. It seems God knows that.

PTSD is caused by more than war and suffered by more than combatants. Peacemakers in war zones also suffer from PTSD, as do women who have been raped, children who have been repeatedly abused. About 8 percent of a general population have experienced PTSD at some time. But the research that has been done is usually by governments as they treat their veterans.

So what is the relationship between my friend, who keeps flashing back to the baby she sat by during her last moments and the soldier who flashes back to that moment with the small girl's body? I'm not a clinician, so I hesitate to draw conclusions.

But I wonder to myself: "My friend has done all she can to alleviate suffering on her road, yet still feels guilt. She'll get over it. She has before."

She'll continue working to make the road safer. But the Marine can't work to improve safety for Iraqi civilians. Maybe one of the reasons why some military veterans heal only after they go back to the country of their combat is because they also have to help stop the suffering. Maybe God knows that we heal by helping others, especially those whom we have hurt.

If humans can't handle war, there must be a better way -- and there is. God showed us, through Christ's death on the cross, that the change of human hearts comes only through self-sacrificing, suffering love, not through violence.