In 'After America: Narratives for the Next Global Age,' a new book by National Journal staff correspondent Paul Starobin, the premise is that America has reached the end of a long global ascendancy.

The era of the 'American Century,' famously heralded by media magnate Henry Luce in 1941 is over. American civilization is no longer, as it once was, the economic, political, and cultural model for the world; a new phase of global history is beginning.

The big question is what's next -- and in this regard, the world is pregnant with multiple possibilities, any one of which could triumph.

The book explores five scenarios for the emerging After America world: A global chaos that could be dark or happy; a multipolar order of nation-states, a global Chinese imperium, an age of global city-states, or a universal civilization leading to world government.

Part 1: Chaos

This is the second of a four-part series of excerpts from Starobin's new book, After America: Narratives for the Next Global Age.

The prospect of a multipolar world is a monumental one -- nothing even remotely like it has ever existed. The closest analogue, the nineteenth-century "balance of power" among the great nation-states of that time, was a reflection of a profoundly Eurocentric order. A new multipolar arrangement would be truly global in sweep, engaging America and Russia and also the rising powers of the East. Not only India and China but also Iran -- possibly a nuclear-armed Iran -- could emerge as anchors. Brazil could be a weighty player. A twenty-first century multipolar world could make for an empowerment of large patches of the planet that for centuries have been regarded by the West as barely capable of organizing themselves.

It is easy enough to play with this conception, as in the board game Risk. No doubt new and improbable-sounding alliances would form, as they did in the nineteenth century, when Queen Victoria's Great Britain and Ottoman Turkey paired up to thwart Russian expansionism toward the warm waters of the Black Sea and the Mediterranean. Perhaps in a twenty-first-century "balance of power," a post-Ottoman Turkey and a post-tsarist, post-Soviet Russia would team up to press their interests in regions like the Middle East.

In this kind of fluid geopolitical environment, categories like "North and South" and "East and West" might become less meaningful. This could be a new age of realism, and possibly of regional hegemonies, in which the nation-state, cold of heart, would have no permanent friends but, rather, a shifting cast of allies and rivals. Then again, perhaps like-minded states, let's say the democracies of America and India, would team up to counterbalance the nondemocratic states, like China. That prospect would warm the hearts of many a Pentagon planner, worried about the overstretching of the American military.

But let's not get carried away. There is nothing that organically ordains a multipolar world.... For there to be a multipolar world in the twenty-first century, the modern nation-state, a battered and aging creature owing its birth to the Peace of Westphalia in mid-seventeenth-century Europe, must reassert itself as the essential actor in global politics. It must become the barrier to a dark, After America chaos. It must have octane -- a national spirit -- to power its gears. It must have efficient machinery -- such as modern surveillance techniques -- to keep WMD out of the hands of nonstate terrorist groups and to keep anarchic cyberwarriors from fouling up vital national security and financial communications networks. It must have effective navies to combat pirates on the high seas....

Neoconservatives are right to be concerned that a multipolar world is unlikely to take shape in the image of America's Jeffersonian ideals. China, Russia, Iran, Brazil -- all come from different political and cultural traditions; and the Indian democratic model, for all it owes to the British example, is distinctively its own. And yet, an analogy from the study of economics suggests that a multipolar world might yield America some unexpected geopolitical benefits.

Economic theory, confirmed by practice, teaches that monopoly is bad -- not only for the marketplace but even for the monopolist. The hegemonic economic actor becomes complacent and arrogant, a deadly combination, after the great victory over competitors is won, like IBM after it achieved dominance in the field of mainframe computers. "Big Blue" stopped thinking and missed out on the minicomputer revolution. In the same vein, unipolar America, after its triumph in the Cold War, became geopolitically dumber, as illustrated by its failure to appreciate the consequences of invading Iraq after the 9/11 attacks.

A more competitive geopolitical world may force Washington to wise up, diplomatically speaking, and make a more rigorous accounting of costs and benefits before deciding to risk its precious resources, foremost among them the lives of its soldiers. As counterintuitive as this may sound, a multipolar world actually could make America a more intelligent geopolitical actor -- which would of course be good not only for the world but also for America.

Nor does a multipolar world offer any obvious threat to the economic fortunes of Americans. It needs to be remembered that America is not the only actor with an interest in a global economic order based on capitalism and trade. Canada, Brazil, Western and Eastern Europe, the Middle Eastern petropowers, China, Vietnam, Japan, Australia -- even tsarist-leaning Russia, with its oligarchs -- have a stake in a system in which goods and services can be exchanged.

That system, of course, is at times challenged by protectionist policies brandished by assorted varieties of economic nationalists. But America itself has been guilty of protectionism at times in its history and can no longer be, in any case, the sole guarantor of a liberal economic order. Assuming that the planet does not turn sharply away from market capitalism as the best way to improve living standards, America is as well positioned as any other nation to thrive in the economy of a multipolar world....

There would be no dishonor for America and its people were the world to shift from the age of U.S. dominance to a multipolar order.... Future generations of American schoolchildren could read in their history books the story of how their nation rose to the occasion as Europe started to fracture, how it helped slay the beasts of fascism and communism, and finally, how the liberal order created and policed by America enabled others to prosper and thus allowed America gracefully to retire from a role, with apologies to Henry Luce, which it was never in the country's character to occupy forever. The difficulty, of course, is that it is not in America's sole power to write this new chapter of its history. There are other authors, all across the planet, with a hand in the story.

Reprinted from After America: Narratives for the Next Global Age, by Paul Starobin, with permission of Viking, a division of Penguin Group (USA) Inc.