I think that the difference for me is that of all the dogs I've shared my life with thus far, most (if not all, they were all taken home from shelters) were and are capable of biting a human, but I've never had a dog in my life that I ever wondered whether they had it in them to actually try to kill. Pitbulls are just as sweet as any other breed, but I'd never take one home, just because of what they can (and sometimes will) do