Car and motorcycle accidents are typically pretty nuts, especially if you see a car just cream somebody walking through the crosswalk. I've seen a couple of those and you can pretty much determine the dude is absolutely dead, it sucks, but you do learn from it. Teaches your ass to buckle up!
IED's or killcam footage from an Apache are straight up surreal, they look just like video games do, it's crazy. I never really considered how big an IED actually was before I saw a few clips, a lot of them range from pretty decent single room house sized explosions, enough to take out your average Humvee or lightly armored vehicle, to truckloads of explosives the size of the Oklahoma city bombing! I saw one one time, the camera sitting stationary on a buildings top floor over 3 miles away and the shockwave shook the camera, the explosion probably killed one or two hundred people! These things are nuts because they're booby traps, you don't know wtf happened until you're on the ground bleeding from what used to be your legs!
I don't really know what seeing that kind of stuff does to a persons mind, I don't see how seeing something or hearing a song or reading a story.. could change the way you feel about murder/death. Like I think if I sat down in a room and was forced to watch 1,000 different beheadings, even on the 1,000th one my feelings towards the act would still be "yep, that's horrifuckinble". Wouldn't someone have to already have those kinds of thoughts/feelings inside them?