In October 1945, leading Minneapolis rabbis issued a public appeal to “the Christian conscience,” mourning that millions of Jews had perished “because of indifference.” Two decades later, the Catholic Church responded in a remarkable way — with the 1965 promulgation of Nostra Aetate, the Second Vatican Council’s “Declaration on the Relation of the Church to Non-Christian Religions.” The document marked a turning point. For the first time, the church explicitly condemned antisemitism, rejected the false charge that Jews were collectively responsible for Jesus’s death, affirmed the enduring covenant between God and the Jewish people, and called for friendship and dialogue...