Seems like this could also be explained by short memories. Most westerners, me included, have never lived through true tyranny, we don't know the signs and probably are just too comfortable coasting along, thinking what we have now won't suddenly disappear [1].
We can read history, but it's nothing compared to actually living through it. And I think most American voters don't know their history, and don't bother to inform themselves either, which makes things much worse.