Via First Things:
Kind, good, happy, gentlemanly, secure people never go Nazi. They may be the gentle philosopher whose name is in the Blue Book, or Bill from City College to whom democracy gave a chance to design airplanes–you’ll never make Nazis out of them. But the frustrated and humiliated intellectual, the rich and scared speculator, the spoiled son, the labor tyrant, the fellow who has achieved success by smelling out the wind of success–they would all go Nazi in a crisis.
Believe me, nice people don’t go Nazi. Their race, color, creed, or social condition is not the criterion. It is something in them.
Those who haven’t anything in them to tell them what they like and what they don’t-whether it is breeding, or happiness, or wisdom, or a code, however old-fashioned or however modern, go Nazi. It’s an amusing game. Try it at the next big party you go to.
His Majesty was uncharacteristically quiet when I showed this to him. One can obviously rephrase the question as “Who goes Sith?” and I think that question made him uncomfortable.
My reasons were clear enough: Confused loyalties and a certain amount of fear. Ventriss closely fit the profile of “frustrated and humiliated intellectual”, as did Darth Maul. But it occurs to me that I don’t know why Palpatine went Sith. The question has simply never come up, and he has no desire to talk about it.