Malcolm X wasn't intended to be a comparison to Palpatine, but an indication that for every right, you have a wrong, and for every hero, you have a villain.
As far as one's belief that one's actions are justified, Lucas's commentary in Revenge of the Sith indicates that Palpatine believed himself to be a savior -- hence his frequent references to peace and justice -- and that his actions may have even been noble but that the price was just too high. It's no secret throughout the EU that Palpatine's oppression effectively eliminated planetary disputes, wars, and other conflicts; territory and colonization were expanded; it was, in fact, Thrawn's personal belief that the Empire was a far greater force for order than the New Republic -- that's why he came back: to repair the Empire in order to stabilize the galaxy against the coming invasion from the Yuuzhan Vong. Had the Empire been functioning during the time of the Yuuzhan Vong invasion, it would have been a very short war. The Complete Visual Dictionary confirms Lucas's commentary that Palpatine considered himself a savior.
Personally? I like to discard that idea. Once you've seen Magneto, you've seen all the moral ambiguity in fiction. People can distort facts to facilitate any action. To me, it's far more interesting that someone like Palpatine was raised to abandon notions of right and wrong. He just doesn't care. He's not some cartoonish villain delighting in murder because it's wrong, but because it amuses him. There is a difference. Palpatine is a narcissist, he exists for self-indulgence and self-glorification. He kills, manipulates, and destroys not because he's out to commit every crime there is, but because he's pathologically inclined to do so. This is the depravity of the Sith, and it's entirely possible that even this world could spawn such a personage -- if under the right circumstances.
Which is why I reiterate that Palpatine is such an effective villain.