@FanOfMostEverything  
It seemed to me more like he was disturbed by his son’s budding sociopathic tendencies than baseless paranoia. Admittedly, he handled it horribly. “Keep our friends close, and your potential betrayer close enough and in front of you so you can see every move, while giving them reasons not to do something.”

@FanOfMostEverything  
Makes sense. Tirek was a bit of a brat. And he’s kind of a prick. And a bit stupid too. Why does he want to obliterate Equestria?

There’s just one.

@TheSultanAkbar  
Classic self-fulfilling prophecy: Vorak tried to quash Tirek’s magical gifts, convinced his son would inevitably turn on him. Naturally, feeling as abandoned and scorned by his own family as he did, Tirek had no reason not to turn on his father. Who do you blame, the monster or the one who made him that way?
 
There is also Sendak, the centaur who gave Tirek much of his basic magical education. Including the theory behind draining magic. He’s pretty terrible himself.

@FanOfMostEverything  
How?

Yep

The only other canon example is his father, who is honestly even worse.