It is less appealing, but morally more urgent, to understand the actions of the perpetrators. The moral danger, after all, is never that one might become a victim but that one might be a perpetrator or a bystander. It is tempting to say that a Nazi murderer is beyond the pale of understanding. …Yet to deny a human being his human character is to render ethics impossible.
To yield to this temptation, to find other people inhuman, is to take a step toward, not away from, the Nazi position. To find other people incomprehensible is to abandon the search for understanding, and thus to abandon history.
― Timothy Snyder, Bloodlands: Europe Between Hitler and Stalin