Antony Blinken, the U.S. secretary of state, is on a mission in Australia to reassure the longtime ally that America has its back even as China flexes its muscles in the region. And in a speech Feb. 10 at the University of Melbourne, he made his case with a personal story about how his beloved stepfather rebuilt his life in Melbourne after the Holocaust, a redemption Blinken said underscored shared values. “The reason he was brought back into the world was ultimately because of Australia,” Blinken said of Samuel Pisar, the philosopher and legal scholar whom Blinken has often cited...