If that woman in the video is kicking the shit out of you, and there's blood and all, and you (a guy) defend yourself, YOU are going to jail. It's not supposed to be like that, but it is in reality.
But in this case, she is kicking a small, defenseless animal. If it is one kick, you're still going to jail, for society be woke. BUT she is kicking the dog multiple times in this video.
Why does it matter? If the 1st kick didn't kill or maim the dog, the other 5+ kicks will. My argument here is that if you quickly 1-hit-KO her after she kicks your dog the first time, maybe you're going to be ok, since you're hitting her to prevent her from further hurting your dog, you're doing it to stop a crime and prevent irreparable damage.