We did vote for Bush, you know. Twice. I don’t think its that far a stretch to say we'd elect Doom if given half a chance.
I vote for Emperor Palpatine
I didn’t list Palpatine on purpose. He is just a bad a dictator as Doom or Gestahl, but society under him was so broken, repressed, and dissatisfied that the movement that would eventually topple his reign came from within. By contrast, Doom is still ruler of Latervia, a prosperous nation considered by the world to be a superpower despite being smaller that Rhode Island. All in game evidence strongly suggest that Gestahl's Empire was similarly prosperous. The resistance again the Empire came from without in the form of the Returners, and had Kefka not lost his damn mind said resistance would have failed.