Accepting the Republican nomination for president in 1988, George H.W. Bush decried those who see “America as another pleasant country on the U.N. roll call, somewhere between Albania and Zimbabwe.” In doing so, he spoke to an intrinsic belief in the America’s national culture that ours is a unique nation with a special role in the world, “a shining city on the hill,” a chosen people among the world’s states. Yet, during his son’s presidency, an opposing view has taken hold among vocal commentators and academics — left, right, and center — who hold America to be just another domineering empire in the roll call of human history.

The latest book to pick up this theme is “The Second World: Empires and Influence in the New Global Order” by Parag Khanna of the New America Foundation, a left-leaning think tank based in Washington. For Mr. Khanna, America is but one of the three great empires of this new century, joining China and the European Union in a race to amass vassal states from the nations of what he terms “the second world” — those countries that are neither failed states nor fully developed.

While none of this is novel, Mr. Khanna’s book is written with ambition, scope, and verve that sets it apart from the usual foreign policy tome. Mr. Khanna spent two years traveling to 40 countries around the world and his work is greatly enriched by his ability to take the reader on a geopolitical tour of every continent — even if his interviews are disproportionately with government officials and public intellectuals on the one hand and his taxi drivers on the other.

As opposed to the tiny tinkers and careful cowardice of much of what passes for vision among contemporary policy writing, Mr. Khanna’s work is confident in his predictions and bold in his recommendations — flatly asserting that “China will heed no calls for democratization or any other systemic change” until 2050 and calling on the United States to create a “North American Community” with “massive” investment in Mexico’s infrastructure and development.

But what is most exceptional about “The Second World” is its firm grounding in history — the immutable grooves that delimit a nation’s options and define its people’s world view. From Ptolemy to Toynbee, history’s actors march across Mr. Khanna’s pages.

Yet it is this long-view virtue that makes the book’s central deficit all the more glaring. Because, for all its admirable qualities, there is a central contradiction at the core of “The Second World”: while Mr. Khanna sees the broad sweep of history when assessing nations around the world, he sees America only through the lens of the present moment, as a wounded hyper-power. Like the handwringers of the late 1970s who could not imagine a resurgent America during the mealy-mouthed, malaise-filled Carter presidency, Mr. Khanna presents America only as it is — overextended and resented — and simply assumes that this is how it must remain.

This is no mere oversight on his part. His is an America in decline, one being rapidly eclipsed by the European Union and China; “a superpower whose intelligence does not match its aspirations”; a country that is “merely one of several competing vendors or brands on the catwalk of credibility” that has little recourse but to sit by and watch “as its military, fiscal, and moral leverage diminishes” and it slips from the first world of developed countries into the flailing second world of countries such as Brazil and Malaysia.

“It would be a step down for most Japanese and Germans to live like Americans, since their countries are the two wealthiest and most advanced — and least unequal — large countries in the world,” Mr. Khanna writes, and when he looks out at the country he calls home, he sees a nation descending into debt and depression, one where “the super-rich live in economic bubbles” while a “materialist frenzy … for holiday presents — sometimes even resulting in fatalities — begins each year at Thanksgiving (if not earlier).”

Mr. Khanna’s America is “a nation of privatized privilege” where “skewed societal structures actually favor the perpetuation of inequality”; a racist, nativist, obese country in which “the primary reason Americans don’t support a welfare state to support the poor is that the poor are disproportionately minorities”; a crass, cleaved country of illiterate, fearful citizens where “populist politicians from the South” have imported their “underhanded ways” into Washington while rampant Christianity “has led to national polarization and even “disenlightenment”; a literally crumbling country that has become “the world’s largest penal colony” and that entertains itself “by death” with “police car chases, wasteful motor sports, and human cockfighting becoming the most popular spectator activities.” Mr. Khanna looks down on an America that is full of vice and devoid of virtue; the Roman empire of Caligula and Nero rather than the “empire of liberty” that Jefferson saw and shaped.

If Mr. Khanna’s America can do no right, to him China can do no wrong. “If America is the greatest nation on earth, someone forgot to tell the Chinese.” He even excuses away the Chinese People’s Liberation Army’s violation of worldwide intellectual property rights — something almost universally criticized — by arguing these are at odds with “Chinese/ Confucian culture” and laying blame at the feet of the West’s “hegemonic legal frameworks.” Mr. Khanna dismisses India, the other great rising power in Asia, in a couple of pages and he proudly trumpets the reason: He prefers the orderly despotism of China to India’s chaotic democracy. In fact, it is China’s model of elevating “‘Asian values’ of unified leadership, consensus, and social harmony” over the “discredited” alternatives of “American democracy, capitalism, and individualism” that is central to his enthusiasm for the Middle Kingdom’s imperial march. Mr. Khanna applauds the Chinese for “restoring democracy to its place as a means to an end — not the highest virtue, but just one agenda item among many.”

It is this denigration of democracy that explains how Mr. Khanna can be so hysterical in his denunciations of America and ahistorical in his assessment of this country’s capacity for regeneration at home and revitalization abroad. In his view, the world revolves around the twin poles of mercantile commerce and military clashes. Yet while America’s armies may be diminished and its dollar weak, the nation’s historic strength has stemmed primarily from the attraction of people around the world to its democratic ideals. An America that puts the shine back on those ideals and makes them relevant to struggling citizens in the countries Mr. Khanna visited would be a nation that is no mere competing empire but, once again, one comfortable in the mantle of “leader of the free world.”

Mr. Cherny is the editor of Democracy and the author of the forthcoming “The Candy Bombers: The Untold Story of the Berlin Airlift and America’s Finest Hour.”