In this year’s Park University Hauptmann Lecture, international policy expert Robert Jervis maintains that though the United States is now unusually secure, there remains a widespread sense among both policy elites and the general public that the world is in fact deeply threatening. How are we to resolve this puzzle? Jervis is the Adlai E. Stevenson Professor of International Politics at Columbia University and past president of the American Political Science Association. Among his books are The Meaning of the Nuclear Revolution and Perception and Misperception in International Politics.