Bremmer has best identified this new twist to the story of globalization in his book The End of the Free Market. The title is a misnomer. The book is really about the rise of state capitalism, also the subject of a recent essay by him in this magazine. Whereas 20 years ago, the list of the largest companies in the world was dominated by private firms, it is now dominated by state-owned entities, many from emerging markets. China's state-owned companies now not only utterly dominate its economy -- of the country's top 100 companies, 99 are state controlled -- but also increasingly play a large role on the global landscape. They play by different rules and have different goals than do private corporations from the West.

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.