Of course dogs can be dangerous. They're descended from wolves, which are the apex predator in their natural environment. We haven't devolved them THAT much.
I also agree that dogs should be kept on a leash, or in a fence, etc etc. Not only does it prevent attacks, but it can save the dog's live because THEY can't be attacked or hit by a car.
However, the point of this thread is that one breed isn't necessarily more dangerous than another. Laws confining dogs to leashes or fences is fine and logical, but banning an entire breed is not. True, pit and rotti attacks tend to be pretty bad, but there was a labrador retriever (a well-loved family breed, I'm sure you know) that tore a woman's face up in Germany, and there are accounts of people being killed by Yorkshire terriers, Pomeranians, and dachsunds. I don't see any breed bans on those four. Dog confiscations should be limited to dogs that are ACTUALLY a problem.