In Afghanistan  I served as a Navy corpsman (combat medic) I never fired a weapon in combat  but I did treat gunshot and fragmentation wounds The heat  the sweat  the smell of filth  the fear and danger  the long hours on the road  the mutual distrust of the local populace  the belief that the next time we left the wire would be the time we’d get hit  the four or five instances of absolute terror spread out over a yearlong deployment – these were the things that gave me pause and caused me to desire and seek numbness