My small, frightened, rescue mixed-breed was attacked by other free(well-bred) dogs whilst he was on the lead 2 years ago. His response was to start to go for them first - he really wanted to inflict damage - and my first response was to muzzle him. In a week he rubbed his nose and mouth on the ground to a bleeding mess and I resolved that he would never be muzzled again. Some dogs can't take it.
It has taken a long, long time but he now has canine companions and trusts us to protect him. You cannot judge all dogs by one or two attacks - horrific though they are.
Locally there are two large, terrifying-looking Staffies. - now I have got to know them they are gentle, friendly, well-trained dogs. No excuses for owners who do not know/control their dogs - none at all - but there will always be idiot owners who acquire dogs they do not understand. Hard to legislate for that.
No, I don't approve of breeding and using dogs as weapons, but you simply can't categorise certain breeds without categorising pairings with certain types of owner. It is impossible and penalises the dogs - not the irresponsible owners.