Uncomfortable...

O'brien writes,

His jaw was in his throat , his upper lip and teeth were gone , his one eye was shut, his other eye was a star-shaped hole, his eyebrows were thin and arched like a women's, his nose was undamaged, there was a slight tear at the lobe of one ear, his clean black hair was swept upward into a cowlick at the rear the skull, his forehead was lightly freckled , his fingernails were clean the skin at his left cheek peeled back in three ragged stripes, his right cheek...his neck was open to the spinal cord and the blood there was thick and shiny and it was this wound that had killed him.(118)       

O'brien reveals that war is uncomfortable and by being in the middle of the war there will be a time where you approach killing someone, then after all these traumatic things happen it will change you as person, maybe leaving you with PTD, because you are emotionally scarred leaving those memories stuck in your head. Then it really shows how it's uncomfortable by the word choice he had chose to describe the dead boy in the story. Leaving you with a vivid image.