Woodrow Wilson was wrong about many things, but he was a veritable hedgehog about One Big Thing: the principle of national self-determination. When it came to his dream of the League of Nations, Wilson was a utopian romantic; but on the question of how to draw national political boundaries, he was a Founding Father of what may be called National Realism.

National Realism comprehends and respects the perhaps tragic, but nevertheless undeniable, fact that most people are deeply attached to collective identities and aspirations. It accepts as both natural and important that psychological well-being would be rooted in a terroir, a set of traditions or other mythologies about who people are and where they come from, that can serve as a source of meaning and self-understanding, as well as social cohesion. It acknowledges that nationalism is a fixture of modern social and political reality.

The idea that a self-described people should have the right to determine its own collective destiny was once considered progressive. Nineteenth-century liberal nationalists like Giuseppe Mazzini in Italy and Ernest Renan in France saw in the nation-state the fullest political expression of peoplehood, a true source of law and legitimacy, a celebration of diversity, and a font of culture, art, and human flourishing. The idea of national self-determination also resonated with the American Founding and with the Declaration of Independence, which proclaimed that governments derive their powers from the consent of the governed and found in Natural Law the right for one people to “dissolve the political bands which have connected it with another, and to assume among the powers of the earth the separate and equal station to which the Laws of Nature and of Nature’s God entitle them.” For good or ill, the French Revolution had awakened modern ethnic self-awareness among European peoples, and ever since, nationalism has been the most robust political force in international affairs. Nationalism is a property of modern nation states, the same way that gravity is a property of physical matter. It is unwise to underestimate its power.

Diversity is now, supposedly, the primus inter pares of our political values. But ethnic and racial diversity, in all its colorful pageantry, is traditionally associated with empires, not republics. Diversity brings to mind Barbara Tuchman’s description of Queen Victoria’s Diamond Jubilee, with its splendid processions of Royal Nigerian Constabulary, Borneo Dyak Police, turbaned and bearded Lancers of Khapurthala and Badnagar, Zaptichs from Cyprus with their tasseled fezzes and black-maned ponies, Houssas from the Gold Coast, Chinese from Hong Kong, and Malays from Singapore, all paying homage to the great monarch. Imperial Rome was an equally spectacular kaleidoscope of nations and religions. By contrast, republican Rome was merely, austerely, Roman.

As a good Progressive, Wilson understood that modern democratic government is incompatible with multi-ethnic empire. But it took the cataclysmic breakdown of the Old World empires in the meat-grinder of World War I to bring the idea of national self-determination into political focus. It would be wise to remember that that civilization-shattering conflict was blamed in large part on the lack of congruence between state and ethnic boundaries. Most of Wilson’s famous Fourteen Points, outlined 101 years ago this month, were dedicated to correcting this discrepancy on the basis of national self-determination.

The self-determination principle was realized only imperfectly in the Treaty of Versailles, thus setting the stage for the even more destructive Second World War. But after World War II national self-determination became a core universal principle of human rights and international law. It was prominent in the Atlantic Charter and in the Dumbarton Oaks proposals on which the United Nations Charter was based.

It is a part of the Great Unlearning of our age that today’s progressives are forgetting the hard lessons that elevated national self-determination to center stage. Visceral hostility to the national idea is nearly universal among the West’s cosmopolitan ruling elites, who conflate it with racism and bigotry and blame it for the catastrophes of the first half of the twentieth century. The upper reaches of our social strata are composed increasingly of a class of transnationals who hold a passport of convenience (or three), and seem to drift along from San Francisco to Singapore to London to Hong Kong, equally at home in each, without permanent attachment to any. Today, a banker in New York has more in common with a management consultant in Tokyo or a lawyer in Dubai than with a soybean farmer in Nebraska or an auto mechanic in Jacksonville. The transnationals share few common assumptions, beliefs, and aspirations with their geographical compatriots from the lower orders, and they have little use for the nation-state, with its flag-waving, jingoism, and other sentimental expressions of folkish unity. History, it seems, continues to mock poor Karl Marx, who proclaimed that the proletariat has no country. As the Brexit vote and Donald Trump’s election clearly show, it is in fact the haute bourgeoisie that has no country; the proles are deeply attached to theirs.

Whether ethnic diversity is compatible with democratic republican government is open to question, though it is considered impolite, or worse, to raise that question. Democracy requires a demos. Truly free, democratic, and stable multiethnic societies are rare, as the Europeans are learning again. There’s Switzerland, sure, but a core principle of the Swiss solution is separation: the country’s four ethnicities are mostly concentrated in their own cantons. Switzerland is a highly decentralized confederacy, where most political issues get decided at the canton level, which minimizes ethnic and regional tensions. The federal government in Bern is practically invisible; most Swiss can’t name their country’s president. This is not a model easily replicated.

The history of the United States does not convincingly prove that ethnic diversity is part and parcel with democracy. Ask a random man in the street of any blue-state city what the purpose of America is, and he’s likely to tell you that it’s immigration—though the word appears nowhere in the founding documents. The U.S. was, from its beginnings, multiethnic, multiracial, multi-religious, and multilingual. But until recently, this background condition was not seen as the font of our national strength. Rather, for most of our history, it was a problem to be overcome through nation-building and assimilation, which America excelled at. By the early 1960s, United States had come close to creating its own unique national ethnicity, albeit one that starkly excluded African-Americans. But even this exception seemed to be moving rapidly toward resolution before the country gave up on nation-building in the late 1960s. One can make a strong case that the early Civil Rights movement was a product of the mid-century high-water mark of American nationalism. Listen to Martin Luther King’s “I Have a Dream” speech; it’s striking how classically nationalist it is, from its evocation of the country’s geographical features to the reaffirmation of its basic creed of freedom, equality, and individual rights, to its Old Testament rhetoric rooted in John Winthrop’s Puritanism.

Speaking in South Africa last summer to commemorate the 100th anniversary of Nelson Mandela’s birth, Barack Obama offered a progressive riposte to National Realism from the position of romantic trans-nationalism. “The countries which rely on rabid nationalism and xenophobia and doctrines of tribal, racial or religious superiority as their main organizing principle—the thing that holds people together—eventually those countries find themselves consumed by civil war or external war,” intoned Obama, who, oblivious to irony, spoke these words standing next to South African President Cyril Ramaphosa, whose government was in the process of introducing legislation to expropriate land from whites without compensation. The past quarter-century has witnessed South Africa’s slow-motion descent into Rhodesian-style chaos, majoritarian despotism, and racial payback. White South Africans, especially the young, are fleeing, some 800,000 having emigrated since the end of Apartheid. Building a functioning multiethnic, multiracial democracy is very hard indeed.

In moments of clarity, when they are not reflexively accusing their opponents of racism, today’s progressives object to nationalism on the grounds that it is outmoded, “socially constructed,” contingent, and subjective—that nations are, in the words of one classic text on the subject, “imagined communities.” But even if something is imagined and socially constructed, it does not necessarily follow that it needs to be reimagined and deconstructed. And good luck explaining to an Orthodox Jew, a Tibetan, or a Catalan that their national identities are just atavistic attachments and impediments to world peace.

One day, perhaps, we will live up to Obama’s soaring rhetoric and fulfill the dream of universal brotherhood. Until then, we live in the world as it is. The tragic virtue of National Realism is that it contains the wisdom that public policy is most effective when it works with the grain of human nature, not against it. Societies are ecosystems. Don’t subject them to diversity shock through hare-brained utopian open-borders experiments cooked up by economists and politicians. Overcoming our irrational tendencies is a worthy individual goal, but the road to anti-human hell is paved with large-scale attempts to eliminate them altogether. The twentieth century should have taught us something about this.

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