Honestly, what I think should happen is licensing of some sort being a requirement before dog ownership. It's not the dog's fault, its the owners fault. Poor training, poor socialisation create the problem.
Saying you can't own a certain breed of dog because they are large is like saying you cant own a big truck or a suv or a fast car because a little hybrid is fast enough for our speed limits.
Imagine you were required to pass an exam for having kids? That'd be awesome
</sarcasm>