ITT: Heroes turned into villains.
I'll start with a classic example.
This is even better example.
Just making Iraq great.
Petain did literally nothing wrong. De Gaul was in the wrong in this case and proved it by not executing Petain. He knew in his heart he had fucked up and France still hasn't recovered.
Do you mean heros that are viewed as villains or people who started out good and then turned evil?