For decades, Liliana Segre visited Italian classrooms to recount her expulsion from school under Benito Mussolini’s anti-Semitic racial laws, her doomed attempt to flee Nazi-controlled Italy, her deportation from Milan’s train station to the death camps of Auschwitz. Her plain-spoken testimony about gas chambers, tattooed arms, casual atrocities and the murders of her father, grandparents and thousands of other Italian Jews made her the conscience and living memory of a country that often prefers not to remember. Now she is wondering if it was all wasted breath. “Why did I suffer for 30 years to share intimate things of my...