The problem is not the breed of dog. The problem is that the dog is loose. Any breed of dog can be dangerous. Any loose dog is dangerous even if it is a nice dog Ė they cause car accidents some resulting in the death of the occupants of the car.
When I walk my dogs I always carry a backpack with water and first-aid kit. I also have a walking stick (large brass knob on the end) and Grizzly Bear Pepper Spray: Counter Assault Bear Deterrent Pepper Spray, The Original "Grizzly Tough" Pepper Spray! (also Wasp spray is good because it sprays a good distance, though the recipient WILL need medical attention to avoid blindness if it gets in their eyes). Mace (tear gas) is not effective on dogs.
My dogs know to get behind me (one of them is a Pit) as I deal with the loose dog since I am the scary one. Loud shouting, with your stick will make most dogs back off. Dogs will remember you and the bear spray for a long time and avoid you and yours.
Donít run! Dogs are hardwired to chase things that run! Even nice dogs will nip at your heels. A pack of dogs is much more dangerous than a lone dog. Even a nice dog in a pack can behave aggressively.
If I see someone who is not doing a good job of safely handling their Pit Bull, I talk to them about the unjustified reputation of the breed (perpetuated and exacerbated by the media) being responsible for the killing of thousands of these wonderful dogs. The owners need to make their dogs into ambassadors of the breed. Most people with their out-of-control dogs look at me (female), and my well behaved dogs (one a Pit Bull type) and choose to become better handler/owners. I usually get a lot of questions about handling/training.
It is always the owner who is the problem, not the breed of dog. Any dog owned by an irresponsible person is always dangerous.
One of the advantages of living in a small town: if the police see you being a responsible dog owner, and get to know you, they WILL come when you call to tell them about a dangerous dog on the loose.
Shooting is a last resort.