I used to dislike dogs due to an experience as a kid, so when I would get chased by a dog of any size, I'd spaz out. There was one old lady who would let her dog run at me every day. I told her, "If this dog comes at me again, I am going to kick it." Sure enough, the next day, it ran after me, so I kicked it...it wasn't trying to be mean. It wanted to play. Now that I've had dogs of my own, if someone did that to my dog, I'd be livid. It's not the dog's fault, it's the owners. So, basically, if the dog isn't posing an actual threat, no, you shouldn't kick it...you can call the cops on the owners if it happens repeatedly, though. With that said, I've been chased by big dogs, too, and I think protecting yourself is much more justifiable in that case, even if you aren't certain if the dog is attacking or playing.