I think it’s more pertinent to note that as a group primate species our hardwired instinct is always to play follow-the-leader. As most people aren’t very bright, simplistic messages have mass appeal whereas anyone attempting to convey complex messages will be ignored. Demagogues know these truths instinctively and use them to manipulate vast numbers of ordinary people.
Thus “we’ve seen the enemy, and it’s us” is a simple matter of fact. We, the nice ordinary well-meaning church-going people, become instruments of evil with absurd ease. Presumably few of those brutalizing small children and throwing people into concentration camps in the name of US border security think of themselves as evil, just as few Nazi concentration camp guards thought of themselves as evil. In both cases the ordinary people are “just doing their jobs.”
There was nothing special about Nazi Germany. We’ve seen the same behavior so many times in history. Ordinary French people were happy to do evil acts against Huguenots, the Inquisitors were ably assisted by ordinary people in their long reign of terror, Stalin found no difficulty in getting millions of Russians to collaborate in his multiple horrors and Mao in China was never short of ordinary Chinese to commit violence on an astonishing scale.
What we need to understand is that we’re a small-brained ape species hardwired by hundreds of thousands of years of evolution to obey purported authority figures without question. When we understand that, we will no longer have misguided notions about “behaving in a moral fashion when confronted with evil” etc. and we will therefore (i) recognize the danger signs far sooner, and (ii) be more able to formulate effective, as opposed to hopelessly ineffectual, strategies for minimizing the harms we so readily impose on others merely because some shouty person on a podium tells us we should do so.