“Where does the story of Auschwitz begin?” asked our guide as we walked towards the Arbeit Macht Frei sign marking the entrance to the former death and concentration camp. With the birth of Adolf Hitler? With the codifying of Nazi ideology? With the first deportation of Polish prisoners to the military barracks that became a killing factory? There were no right answers, he said. Last month, less than 48 hours after Hamas militants slaughtered men, women and children in Israel, and as references to “pogroms” and “massacres” were resurfacing in the headlines, I found myself taking part in a long-planned...