To argue against the widely proclaimed idea of American decline, as this book does, might seem a lonely task. After all, the problems are real and serious. Yet if we take a longer view, much of the discourse about decline appears exaggerated, hyperbolic, and ahistorical. Why? First, because of the deep underlying strengths of the United States. These include not only size, population, demography, and resources, but also the scale and importance of its economy and financial markets, its scientific research and technology, its competitiveness, its military power, and its attractiveness to talented immigrants. Second, there is the weight of history and of American exceptionalism. Throughout its history, the United States has repeatedly faced and eventually overcome daunting challenges and crises. Contrary to a prevailing pessimism, there is nothing inevitable about American decline. Flexibility, adaptability, and the capacity for course correction provide the United States with a unique resilience that has proved invaluable in the past and will do so in the future. Ultimately, the ability to avoid serious decline is less a question of material factors than of policy, leadership, and political will.