Last week, Russian troops withdrew from Bucha, a suburb of the Ukrainian capital of Kyiv. Ukrainians returning to the city discovered the horrific aftermath. According to President Volodymyr Zelensky, more than three hundred civilians in the city were killed. Investigators have found evidence of torture, rape, beheading, dismemberment, and the intentional burning of corpses. A mass grave was dug to accommodate the bodies. Zelensky has referred to the massacre as evidence of genocide. Philip Gourevitch, a New Yorker staff writer, has written for the magazine about the genocides in Rwanda and Cambodia. He joins Dorothy Wickenden to discuss his past reporting, why the “never again” discourse around genocides has failed to prevent them, and whether further war crimes in Ukraine are inevitable.