The media has given this image of the pit bull. Pit bulls are a favorite in dog fighting because of their strength and, when trained, aggressiveness. The a-holes who would train dogs in this way are evil, not the dogs. Judging all of a breed because of the actions by irresponsible owners isn't fair. I've seen some humans who have done absolutely horrendous, vicious, and violent things. If I tell you they were all of one race or group (they weren't, but if I did), should we execute all of that race/group? Those innocent, well-trained and haven't shown violence shouldn't be put down because of the actions of some.

As I said, pit bulls can also be heroes:

Lilly the Hero Pit Bull
Pit Bull Heroes Hall of Fame | BSL News