Reintroducing a grizzly bear into what is their natural habitat is a completely different issue from a dog that can kill living next door to you.
Also, have you had the opportunity to visit a 6 year old girl in the hospital who will probably shudder every time she looks in the mirror for the rest of her life, thanks to the family's kind-hearted and wouldn't-hurt-a-flea pitbull that nearly destroyed her face? But I guess she is just being a cry-baby. All the dad could say was "I can't believe it, he would never do this, never. Never. Never." I am glad that her pain is worth it to you so you can live a more dangerous and thrilling life, or whatever drivel that was. Because it still does not address the issue at hand. But I guess on second thought it does. Your opinion is that this kind of "accident" is fully acceptable to make sure everyone else can have their freedom to do whatever romantic/adventurous/fun thing they want with their dogs, so nothing need be done at all. You are entitled to that opinion. I respectfully disagree.
In talking to some friends about this subject one of the tough things in legislating this kind of regulation is how often the attacks happen to family that own the dog, which is quite frequent. This makes a harsh criminal sentence not a very good deterrent as they will just figure, well I never let anyone else around my pit, so I don't need to worry about it, until it kills grandma one fine summer afternoon.
I wondered about requiring large-breed dogs to be registered and requiring owners to pay relatively large fees to do so, and then requiring regular vet visits in which the vet evaluates the dog's temperament and training and if it is deemed to be insufficient then it can be taken and put down and the owner fined a large-ish amount. There could be jail time and/or fines for people who own these breeds outside the system. The up-front registration requirement will ensure that only people who are very serious about having a dog of this and other large breeds will have one, rather than just picking one up from their cousin's sister because pits are so "ghetto-cool" or whatever. But then I think about my friend who is a registered breeder and trainer, whose dog was his pet for 10 years, very well trained and behaved, until some to this day unknown thing prompted it to attack the girl and chew on her face right in front of him and his wife. This kind of registration would do nothing to stop that. But I would be in favor of something like this over just outright banning the breed if it could be pulled off.