This all got a bit out of hand no? I have no doubt that Junglist probably wouldn't hurt the the person who killed this dog, if it was indeed a person. But she is not BU to wish it, nor is the op. It is a natural human response to such terrible acts surely? I'd feel the same if I knew the dog. Poor dog. I hope it didn't suffer
Though I agree there are many things that could have happened to the dog, being deliberately attacked, is the least likely. More likely that it was a cyclist or passer by acting out of fear who was too ashamed/twattish to stop and explain or try to help the animal.
I love dogs, but when I was walking to the shop earlier I was accosted by a very bouncy greyhound puppy. All fine. Puppies are yummy. When it's adult mate jumped out of the car and ran at me growling, however, I have to admit the thought of kicking it away if it got closer did cross my mind. This was a larger dog. A JRT wouldn't need kicking away. A foot placed gently but firmly on it's side would hold it down while you maneged to control it. JRTs are very small. Saying that though I am not afraid of dogs. Particularly small terriers. Some one who was afraid wouldn't be thinking rationally if they were approached by a growling terrier or even just a running terrier, if their fear was great enough.
Wrt the dog being dragged away and the woman not helping, I'd have thought it was sheer laziness that stopped her stepping in rather than fear. If I heard a dog screaming in pain I'd go and investigate immediately as my first instinct would be that it had gotten trapped or accidentially hurt. It wouldn't even cross my mind that some-one couldn't be beating it. Why would it? It is not normal, everyday behavior.
Who posted that link? While I have every sympathy for that poor little girl, what was she doing close enough to the dog to get her face hurt in the first place? You should never approach an unknown tethered dog unless the owner says it is okay, lest of all out your face close to one.