As German Soldiers died, so Jews would be required to do so

The Holocaust repeated the Trauma of the First World War:
Millions of Human beings slaughtered by the nation state

Richard Koenigsberg

Hitler (Mein Kampf, 1924): “If at the beginning of the War and during the War twelve or fifteen thousand of these Hebrew corrupters of the people had been held under poison gas, as happened to hundreds of thousands of our very best German workers in the field, the sacrifice of millions at the front would not have been in vain.”

As Hitler and his colleagues had been held under poison gas in the First World War, so Jews were held under poison gas in the Holocaust. Hitler repeated the trauma he and his colleagues (as well as enemy soldiers) had suffered, with Jews substituting for soldiers.

The Holocaust was a repetition of the First World War. We no longer need to view the Holocaust as "incomprehensible:" it was a repeat of what already had occurred in the First World War: millions of human beings slaughtered by nation-states.