Too many of our vets returning from the Middle East are experiencing PTSD as our Vietnam vets have. I have been studying the issue of PTSD for some time. I was lucky and didn’t experience combat during my own Korean War service.
My best resource is a book by Lt. Col. Dave Grossman, “On Killing”. (From Amazon and other used book services) Dave fought as a grunt, commanded troops as an officer, researched battlefield trauma and has counseled troops with PTSD. He has explored man’s nature and what we do under combat conditions and the results afterwards. Dave concludes that humans are not natural born killers and that killing another human is a very difficult thing to do. It is difficult to pull the trigger looking at the enemy in your sights. Watching and hearing him die is very traumatic. Killing by remote control such as firing a cannon or dropping a bomb is easier because you don’t see the damage that you have done even though you often kill many more people.
In earlier wars few soldiers actually shot at the enemy. Some shot over the heads of the enemy and others did not shoot at all. We have to be trained to kill.