I suspect many of us, with a certain feeling of self righteousness, deplore the wickedness of the Holocaust, which saw millions murdered at the hands of their fellowmen. Perhaps we ask how a large group of people could be sold on the need to exterminate men, women, and children. What were these people thinking that would have justified such a thing in their own minds?
Maybe we conclude that a great number of Germans were just exceedingly wicked as compared with the average individual. These were, perhaps, so bad that they simply reveled in evil doing, needing no mental justification at all. Even casual contact with the German people will put this kind of reasoning to rest. They are just like us, kind, gracious, and honest.
Personally, I suspect something besides the enjoyment of pure evil was at play behind the relative indifference shown by many to the plight of the Jews. Hitler and the Nazis, using vast, well orchestrated rallies and hateful rhetoric, convinced a significant portion of the population that the Jews were an existential threat to Germany. Unless these people were eliminated, Germany was doomed to extinction. In a period of economic uncertainty and fearfulness, many were eager to find someone to blame for their troubles, some concrete action they could take to improve their lot in the world. Hitler and his henchmen handed out the necessary scapegoat, and many bought into the story. Others were merely swept along by the force of the emotional outpouring which the anti-Jewish hatemongers created.
As we consider the thinking that somehow justified the Holocaust for its perpetrators, we need to recognize the general corrosiveness of labeling groups as an existential threat. In that regard, we should be quick to reject the unrestrained and bombastic political rhetoric which is always a major part of justifying an evil public policy.
Sadly, the church in Germany did not effectively counteract the poisonous reasoning which saw extermination of Jews as a public good, as the proverbial necessary evil. One suspects that some in that church actually added to the hateful message. I hope that decades from now we don't end up regretting our own version of Holocaust thinking and the church's complicity in another "necessary evil".