"Boys with a normal viewpoint were taken out of the fields and offices and factories and classrooms and put into the ranks. There they were remolded; they were made over; they were made to "about face"; to regard murder as the order of the day. They were put shoulder to shoulder and, through mass psychology, they were entirely changed. We used them for a couple of years and trained them to think nothing at all of killing or of being killed.  Then, suddenly, we discharged them and told them to make another "about face" ! This time they had to do their own readjustment, sans [without] mass psychology, sans officers’ aid and advice and sans nation-wide propaganda. We didn’t need them any more."

-from "War is a Racket" by U.S. Marine Corp. Gen. Smedley Butler, who was awarded the Congressional Medal of Honor twice.  http://thoughtcrimeradio.net/2015/11/pdf-war-is-a-racket-by-gen-smedley-butler/