In retrospect I think I understand now that nearly all the WW 2 veterans I was close to when I was growing up were in some way traumatized by that war. For some this trauma played out as anger and callousness to human suffering.
For most the trauma manifested itself in alcoholism and tobacco addiction. I don't mean a pack a day, I mean three or four packs. The two men I have in mind, one a father of a best friend, the other a mentor in the newspaper world, perished before their time from early strokes.
My dad was also traumatized, but in an odd way that I didn't learn about until he was in old man. He was in his thirties, a father of two, when he was drafted in the navy late in the war. He was only in nine months when the war ended and he was sent home, and he saw no military action, and yet he was all fucked up upon his return. I was four years old. His behavior was zombie-like. He would get dressed up in suit and tie every morning and sit by the window all day. He was not abusive. Quite the opposite. He was remote and noncommittal. It was nine months before he was well enough to go back to work as a weaver in a textile mill.
Eventually, he was just fine, but it took a long time. Also, his personality changed. As a young man my dad was a daredevil. He raced motorcycles and was a ski jumper. He returned from the war timid and very quiet, a man who avoided conflict of any kind.
Finally, in his eighties after my mother had died and my dad moved in with my family he told me the story of what screwed him up.
He was in the Navy, a seaman who worked in the engine room on a small troop ship in the Philippine Islands. The ship hit a rock and found itself stranded. They were there five days until another ship arrived to pull them off.
My dad was alone in the engine room doing his job when the ship lurched to one side and threw him down. He tried to get out, but discovered that the hatch had been locked. He was trapped down there. What traumatized him was not that he was locked in--he understood that if his compartment was flooded it had to be sealed off to save the rest of ship; what traumatized him was that they didn't tell him that they had locked him. He would have volunteered. They denied him a chance to be a little bit of a hero. That distrust of authority (who distrusted him) alienated him, caused him to withdraw from humanity for some time.
It wasn't just the fathers who were traumatized; I think that the children of the vets were in some way themselves traumatized--or at any rate, shaped--by the absence of their dads during the war and their behavior afterwards. I know I was. I think this affect played itself out in the sixties revolution--sex, drugs, and rock n' roll, in the succeeding counter-culture of the 1970s and in the extreme distrust of government that we see today.
You could argue that war is good for the human spirit. It creates solidarity among the citizenry; it enlivens the society (sex, drugs and rock 'n roll); it fuels research in science projects (atomic bombs); it provides an outlet for aggression; in competition among the sexes it puts women in their place and gives men the edge they crave; it outs cowards like me who are against war.