Eighty years ago, on Jan. 27, 1945, Soviet soldiers opened the gates of Auschwitz-Birkenau and uncovered unimaginable horrors. For the 7,000 prisoners remaining—more than 60,000 had been forced to undertake a death march in the weeks before Allied troops arrived—liberation came as a bitter relief, overshadowed by the harrowing murder of 1.1 million within those gates. This number included 1 million Jews, along with tens of thousands of Poles, Roma and Sinti, Soviet prisoners of war, and others deemed “undesirable” by the Third Reich.

Since then, Auschwitz has become the foremost symbol of the Holocaust’s atrocities. Yet the 80th anniversary of the camp’s liberation reminds the world that the scars of genocide, though deep, are slowly being obscured by time. That creates risks: the Holocaust didn’t begin with mass murder. The dehumanization of Jews progressed gradually from public exclusion to eventual internment to finally extermination. Millions of regular Germans—and Europeans more broadly—facilitated or silently accepted these actions.

As Holocaust survivor Marian Turski warned five years ago at Auschwitz, this sort of indifference in the face of discrimination risks people not even noticing when “an Auschwitz-like catastrophe suddenly befalls you and your descendants.”