I'm going to call someone else an asshole
Why do you want to act that way?
It's not because of any specific actions, he's just naturally an asshole, in general.
It's okay to point out someone's bad behavior if they are being inappropriate, or otherwise just being a jerk, but simply calling someone names is mean.
I'm going to act the way I want to. My reasons are my reasons.
Calling someone names and trying to hurt their feelings for no reason other than you wanting too isn't a good enough reason. It ca really hurt someone to be called names.