I was wondering when someone was gonna bring that up.
If Hitler won, then history would have favored the Allies as villains living in a corrupt, incompetent, genetically inferior, and all in all bad society.
Since we won, we tend to view Nazi society as wrong and evil. Conflicting preferences, but only one won out.
And since we all live in a society that defines evil the way we do, then from an outsider's POV, Palpatine is just Hitler on a much, much grander scale.
I hate this thread. But ush is right: Palps knew he was evil, that is clear from all his expressions, and he used his evil to get his way. He clearly says that he's out to make the Sith rule the universe and Sith only think about themselves. Ergo, case close.
Now, you can add SW related stuff to debate it. If it turns to points of view on good or evil I will close the thread on your OB1 butts.