Maybe it's a bad idea to slaughter innocent people for no reason. It tends to make the people in your immediate vicinity not trust you.
Notice no screeching about the guy who stabbed a kid in a NY synagogue last night before being eliminated buy a good guy with a gun.
Almost the exact same situation except one was put down by a cop and the other was put down by a private security guard.
I was wrong it was a cop who killed the perp in Brooklyn last night. In fact the cop was backing away and retreating even after the guy lunged with the knife. Video at site.
http://www.cnn.com/2014/12/09/us/new-york-synagogue-stabbing/index.html