The current global order appears to be collapsing. Long forgotten challenges, such as the return of great power competition and the specter of nuclear war, demand fresh attention, while novel, complex, and menacing planetary crises ranging from climate and disease to emerging technology loom. Meanwhile, the United States—the most consequential nation in the international system, behaves erratically and seems willing to abandon its decades-long strategy of building strong alliances, countering authoritarianism and supporting openness. How should we understand these unsettling trends? Wonder and Worry offers Francis J. Gavin's best insights on the pressing, fundamental questions we face. Gavin's answers are nuanced, counterintuitive, and often surprisingly optimistic in this incisive and accessible contemporary history for our uncertain age.