I agree with you. Dogs do not snap, they show signs of aggression long before people notice, and sometimes, unfortunately, these signs aren't seen until it's too late. However, once a dog kills a person, regardless of breed or upbringing, the safest thing to do is to have it euthanized. Yes, the dog was probably lashing out in defense and may have been disoriented and in pain, but it still took a life.
It's really sad that even this situation is being viewed as "another dog of peace attack" when really it's about owner and parent responsibility. Everyone knows you don't touch an injured animal because you could get attacked. Perhaps the dog had on previous occasions been caught, but this time it might have been really caught, choking, or the collar being caught could have been cutting him. I have seen injured people lash out at doctors on hospital documentaries.
I have seen injured people lash out at doctors on hospital documentaries.
Yes, it happens. I stopped wearing my lanyard because a patient grabbed it and starting choking me. Lucky for me someone else was in the room to help.
As far as "snapping" goes, humans are good at it. Especially when they feel threatened.