He's an arrogant clown who thinks every Facebook post is an invitation for a rude, often insulting, response.
The classic know-it-all.
Then I found this -- unfortunately, later in the day, after I'd disposed of my unfriendly friend.
It's the best response to such people.
(And to Trump, too.)
You've probably heard or read about it: Studies show that the more confident people are, the greater the likelihoood they are wrong.
Just click over to it, save it and keep it ready to post whenever confronted by an online jerk.
Chances are, I'll see it in response to the blatherings I post here, perhaps even this one.