The Frugal Superpower begins with what Mandelbaum takes to be an important turning point in the history of U.S. foreign policy: September 15, 2008. On that day, it shall be recalled, the investment bank Lehman Brothers collapsed, deepening a worldwide economic downturn. In a work of great clarity and elegance, Mandelbaum looks into the United States' future and into the growing economic constraints on its power. Seven decades of American assertiveness abroad followed World War II, and Pax Americana made the world safer and more prosperous. But the United States can no longer afford to pay for the international security order. Those who have complained about excessive U.S. power may live to worry about a greater threat -- the growing weakness of the United States as it takes up economic challenges at home.
This book is not a work of declinism but an unsparing assessment of the constraints on American power in the years to come. No single power, or concert of powers, Mandelbaum warns, shall step forth to assume the American burden. Humanitarian interventions and military campaigns such as those in Afghanistan and Iraq are not likely to be repeated. Such endeavors, Mandelbaum writes, will be resisted by an "American public worried about increases in the costs and reductions in the benefits of entitlement programs." Americans willed, and paid for, an imperial role in the modern world. And of course they borrowed with abandon; foreign creditors were willing to oblige. But that long run has come to an end. September 15, 2008, will indeed turn out to be a day of great consequence in the history of the American republic abroad.