Anyone who does what he did is performing a stupid act. No amount of angry comments online should cause any well adjusted person to seek out an unimportant conflict. Allowing your emotions to take control of you like this demonstrates mental weakness, not strength.
Also, it is idiotic to invite such aggression on yourself. You do that, and you quite likely remove any legal defense you have when you respond to said aggression with deadly force. Better to allow the idiot to do all of the work, so when you are in court defending your actions, you can point out that you were never the aggressor and you did not invite the aggression onto yourself.