What in everyone's eyes constitutes an 'attack' though?
That is the hardest question in the world to answer!! Because a growly scuffle can be fine in a 'doggy' world, I know Ben will run at growl or nip another dog if it pesters him too much, and I would not class that as an attack - equally if another dog did that to one of mine I would view it in a similar fashion, just dogs sorting themselves out and its best to leave them to do it I always think human intervention can escalate the situation when it is not necessary.
However - for me it depends on the 'breed' of the other dog. And I know that is not going to be a popular answer - becuase it is making a judgment about a breed without taking individual dogs and owenrs into consideration. But I have fears about certain big breeds, eg staffies, dobermans, huskey types (huge huge apoloiges to all you people who have lovely kind examples of these breeds

) but my fear is that with a strong or big dog I wouldn't be able to get it off or pick it up or even do anything much if it was pinning down or drawing blood on one of my boys. I know someone who had a really bitey terrier, and probably much more likely to bite than a big breed, but I wasn't scared of him becasue in my head I imagined if necessary I could pick him up or shove him out of the way. Not necessarily logical perhaps, but the way my head works.
So for me an attack would be a certain breed biting or trying to pin down one of my boys - sorry