I can't even say I would agree with that either, maybe I would go back in time and KNOWING the threat I would implement or try to implement obstacles to prevent him getting to power.
Offer the little bastard an art scholarship in Prague or something.
Even your genuine honest question brings to mind that question "Who is evil?" we always say Hitler and he was but nobody seems to put Stalin and his tubby custard moustache in the same bracket.
Assassinating someone you don't agree with politically is and should be abhorrent IMHO full stop, this murder will give politicians on both sides of the aisle free reign to implement stuff they could never have gotten away with before.