You gotta know your dog, if it needs a leash, it needs a fucking leash, if not not.

I've always had dogs and some used to run towards people, I knew they didn't intend to harm them but people never know the dog's intentions. It's understandable that people react violently.

NOT illegal... nearly every state has a leash law..

The only reason to ever kick a dog - or any other animal - is in a real self-defense situation (or defense of another).

It's usually pretty easy to tell if a dog is approaching you with the intent to attack or not. They give off all sorts of body language signals.