Harvard professor and international relations expert Joseph Nye has had a long and distinguished career, working on the ground in the Carter and Clinton administrations as well as many years teaching foreign policy. His new memoir, A Life in the American Century (Polity Books), is a diary of his life, including his years in the university and government and his thoughts about where the U.S. stands in today's global world order. In this Q&A, Nye talks about his advice for the interim and future president of Harvard in the wake of Claudine Gay's resignation, which countries should be highest on...