Hey Slap,
We had some Washington State Troopers come in and do one of our quarterly safety briefs back in 2002 - they brought in some serious photos - it was very sobering. I think it goes beyond just the actual gore, often its the type of casualties. Seeing a child dead has a more emotional impact then seeing a grown man. I guess that could be because you reflect upon the own things you value most as a parent, and the the idea that those things could be torn away from you in that way is hard to swallow - it tends to stay with you longer.
Best, Rob