No one is saying that we should let dogs do whatever they want, but its too late for punishment. The dog is just not going to comprehend what he did wrong. If he had the bunny in front of the dog, and it was right after the attack he could punish all he wants.

You cant tell me that you believe dogs are as smart as humans (unless youre a PETA fuckhead), so comparing them to us would be like apples an oranges.