I hope nobody gets the wrong impression from my post on how to deal with dog attack. I love dogs and have owned a few. I currently have one who is a great family pet. I agree with all who point to the owner as the negligent party.
However, when confronted unexpectedly by a viscious dog who attacks . . . there is no room for moral considerations. Dogs can kill. If you have a strategy to deal with the attack, particularly when children are present . . . you give yourself the best chance for the best outcome.