The point is that as a society changes, as what’s held sacred and who’s empowered shifts, so do the paths through which evil enters in, the prejudices and blind spots it exploits.
So don’t expect tomorrow’s predators to look like yesterday’s. Don’t expect them to look like the figures your ideology or philosophy or faith would lead you to associate with exploitation.
Expect them, instead, to look like the people whom you yourself would be most likely to respect, most afraid to challenge publicly, or least eager to vilify and hate.
Because your assumptions and pieties are evil’s best opportunity, and your conventional wisdom is what’s most likely to condemn victims to their fate.
From an interview with a (Yugoslavian) guard at Auschwitz:
SPIEGEL: Do you feel a something like a sense of moral guilt?
W.: No. I spoke to them in a friendly manner; I never hit, kicked or killed any. I do not feel like a criminal just because I had to guard them. Germany had invaded Yugoslavia and that was a crime against humanity and international law. Then the Nazis conscripted me and brought me to Auschwitz. And how was I supposed to get away from there? If I had deserted, they would have shot me.
So let’s be clear that this guy should definitely feel moral guilt.
And yet, I don’t know what your grandfather is like but most men I know from that generation express moral views I often find pretty shocking. In the context of his time, is this man’s lack of remorse as surprising even given that we judge it to be horrible?
The key idea, I think, isn’t that people from other eras are evil, it’s that evil takes on a form that is palatable to its time. It is evil all the same and we are just as capable of it today even though we might haughtily look down upon older, ‘backward’ generations.