Cosmopolitanism is under assault from across the political spectrum, both in the United States and abroad. Just yesterday President Donald Trump’s chief strategist, alt-right leader and self-described economic nationalist Steve Bannon, told the Conservative Political Action Conference that “the center core of what we believe [is] that we’re a nation with an economy, not an economy in some global marketplace with open borders, but we’re a nation with a culture and a reason for being,” This is a false alternative of course, but Bannon’s preference for nationalist tribalism is revealing.

The rejection of cosmopolitanism is bad for liberty, peace, and prosperity because they all go hand in hand. The link between liberty and cosmopolitanism is more than conceptual. Of course freedom includes the freedom of individuals to associate peacefully with anyone anywhere of their choosing, which in turn generates peaceful interdependence and prosperity. But the link is also existential: rising generations, no matter what they have been taught by their elders, naturally will be curious about other people and their ways of living, their cultures. They naturally will question what has been presented to them as sacred (even if “secular”) tradition. This will inevitably lead to cultural and material exchanges and hence further social evolution. The “ideal” of a culture insulated from change is a chimera, especially these days; it would be unachievable even if it were desirable — which it most assuredly is not. Even totalitarian states struggle in vain to shut out “subversive” foreign influences, as the old Soviet Union demonstrated.

We may not go so far as Aristophanes and say that “Whirl is king,” but unforeseen change is inevitable and also reasonably assimilable in normal circumstances. In a freed society most change occurs at the margin — the world does not start afresh each day — because no central authority has the power to make society-wide decisions. But with freedom, the cumulative effect of change is dramatic and largely benign.

Original cosmopolitan liberalism, what we call libertarianism today, embodies this fact of life. It embraces it with gusto. Liberty and the prosperity it produces enable us to grapple with — and indeed relish — the uncertain future that, being the product of human action but not human design, spontaneously unfolds before us. Serendipity happens. We can therefore view liberalism as occupying the ground between conservatism/traditionalism and rationalism/Jacobinism.

As F. A. Hayek wrote in “Why I Am Not a Conservative”: “As has often been acknowledged by conservative writers, one of the fundamental traits of the conservative attitude is a fear of change, a timid distrust of the new as such, while the liberal position is based on courage and confidence, on a preparedness to let change run its course even if we cannot predict where it will lead.”

Hayek’s openness to change may seem in conflict with the apparent conservatism of The Constitution of Liberty (1960) and his final book, The Fatal Conceit (1988). (The fatal conceit lies in believing that our principles of moral conduct were originally the product of reason rather than of spontaneous social evolution as people grappled with reality in search of better lives.) But no actual conflict in Hayek exists. (“Why I Am Not a Conservative” is the postscript to The Constitution of Liberty.) In the absence of good cause to depart from traditional practices, one tends to accept those practices because, among other reasons, their longevity may be an evidence of their value. (Longevity is no guarantee of this.) The case for such “conservative” deference dates back at least to Aristotle. (See Roderick Long’s discussion of the importance of endoxa, “the credible opinions handed down” [Stanford Encyclopedia of Philosophy], in his Reason and Value: Aristotle versus Rand. Long’s essay suggests that cultural innovation reasonably begins with defeasible received wisdom as opposed to wholesale rejection of it.) But the good sense in defaulting to credible opinions provides no case for freezing traditions in place, for this would imply an unjustifiable hubris regarding the current state of our knowledge. After all, today’s traditions were once new: how do we know there aren’t hitherto undiscovered better ways to accomplish our ultimate objective, namely, the flourishing of individuals in society? Why would we want to deprive ourselves of the opportunity to learn of such knowledge? And on what grounds do we assume that anything worth knowing is to be found within our national borders? Hence liberal cosmopolitanism, from the Greek suggesting “citizen of the world.” (I’m reminded of Adam Smith’s observation that “the division of labor is limited by the extent of the market.”)

Apparent efforts to romanticize tradition and cultural preservation (aka stagnation) have a way of teaching a different lesson. Think of the beloved musical Fiddler on the Roof, based on the Yiddish stories by Sholem Aleichem. The protagonist, Tevye the dairyman, opens the show by celebrating the tradition that has enabled him and his neighbors (and their forebears) to keep “our balance for many years.” As he explains, “Because of our tradition, everyone here knows who he is and what God expects him to do.” (At the same time he confesses: “You may ask, ‘How did this tradition get started?’ I’ll tell you. I don’t know. But it’s a tradition.”) At sundown on the Sabbath, Tevye and his wife pray that God will keep their five daughters “from the strangers’ ways.”

Yet almost immediately the traditional structure that Tevye believes he can’t survive without begins to crumble at the margin, and he is powerless to prevent it. When he agrees to marry off his eldest daughter, Tzeitel, to the much older butcher, as arranged by the village matchmaker, she begs her father not to force her to go through with the marriage. A year earlier she and her childhood friend, now the village tailor, had secretly agreed to wed as soon as he could afford a sewing machine. (Aside: when the tailor Motel Kamzoil gets his sewing machine he boasts that from now on clothes will be made quickly and perfectly — no more handmade things.There’s an economic lesson in that for another day.) Now under pressure from the matchmaker, Tzeitel asks her father for permission to marry the man she loves. Tevye at first is furious at her impertinence, but when he looks in his daughter’s eyes as she stands by her beloved, he can’t help but relent. His daughter’s happiness outranks tradition. (Before this scene we saw Tevye celebrating the marriage agreement with the butcher by participating in a Russian dance with Russian gentiles in the local tavern, indulging, it would seem, in the strangers’ ways.)

Tzeitel’s break with tradition is only the beginning. Tevye’s second daughter, Hodel, then falls in love with Perchik, a poor young radical teacher from Kiev, the big, strange, distant city. This was the same young visitor whom villagers had denounced as a “radical” for saying that girls should be educated and for dancing with a female (Hodel) at Tzeitel’s wedding. The “attack” on tradition kicks up a notch when Hodel and Perchik decide to marry: they do not ask Tevye for his permission — only for his blessing. He is scandalized at this further blow to the structure, but in one of his trademark dialogues with God, Tevye acknowledges that “our ways also once were new” — a subversive thought for one who wishes to keep his children from the strangers’ ways. Again he relents and gives his blessing (and his permission), explaining to his wife, “It’s a new world, Golde,” one in which people marry for love. He then alarms his wife, whom he had met only on their wedding day, by asking, “Golde, do you love me?” Tevye is clearly warming up to the new world.

But Tevye finally draws the line when his third daughter, Chava, marries a young Russian she has fallen in love with. As he is packing to move his family out of their shetl, Anatevka (from which the tsar has expelled the Jews), he relays his blessing to Chava and her new husband. It is noteworthy that Tevye, like Sholem Aleichem himself, moves to “New York, America” not Palestine. (Tevye’s brother had previously moved to Chicago.)

So even insular little Anatevka could not shield itself from change and the outside world. Was Sholem Aleichem a subversive? If so, many people seem to have missed it. But how can you celebrate traditionalism while showing the virtually inevitable erosion of particular traditions at the hands of the young and free seeking only to be happy? There’s a lesson here for all of us, especially those who seek to “make America great again.”

Whirl is king, despite one’s wishes and efforts. Of course this does not mean that all change is good, but attempting to prevent all change in order to prevent bad change is futile and self-defeating. Moreover, change that one person sees as bad another person may see as good. People should be free to shield themselves against change they do not like, but coercive power must be kept out of the picture.

The history of original liberalism overflows with acknowledgments that openness to change, which is the essence of cosmopolitanism, is vital to flourishing. The free and competitive marketplace of ideas, like the market for goods and services, was championed by early liberals precisely because it was the way to dispel ignorance not just in how we think but in how we live. Thus they showed an appropriate humility — a recognition of the limits of knowledge — in their praise for the free marketplace of ideas.

John Stuart Mill’s On Liberty (1859) is well-known in this regard, so I’ll limit myself to one quotation:

“That mankind are not infallible; that their truths, for the most part, are only half-truths; that unity of opinion, unless resulting from the fullest and freest comparison of opposite opinions, is not desirable, and diversity not an evil, but a good, until mankind are much more capable than at present of recognising all sides of the truth, are principles applicable to men’s modes of action, not less than to their opinions. As it is useful that while mankind are imperfect there should be different opinions, so is it that there should be different experiments of living; that free scope should be given to varieties of character, short of injury to others; and that the worth of different modes of life should be proved practically, when any one thinks fit to try them. It is desirable, in short, that in things which do not primarily concern others, individuality should assert itself. Where, not the person’s own character, but the traditions or customs of other people are the rule of conduct, there is wanting one of the principal ingredients of human happiness, and quite the chief ingredient of individual and social progress.” (Emphasis added.)

To take an earlier example from across the Channel, Charles Dunoyer, a pioneering French radical liberal and one of the originators of class analysis (which Marx explicitly borrowed and distorted), criticized the socialism of Henri de Saint-Simon precisely because it failed to recognize the value of the competitive marketplace of ideas. Dunoyer wrote in 1827 that the Saint-Simonians’ “complaints against what they call the critical system, that is to say, against a general and permanent state of examination, of debate, of competition, attacks society in its most active principle of life, in its most efficacious means of development.” They don’t want to “leav[e] society to itself,” letting it develop “by the free competition of individual efforts.” Yet they contradict themselves by conceding that “free discussion is necessary” sometimes. But if that’s true, Dunoyer asked, what can be the case against freedom?

Dunoyer continued:

“Is there, in the course of centuries, a single instant where society does not tend, in a multitude of ways, to modify its ideas, to change its manner of existence? To accuse liberty of what remains of confusion in moral and social doctrines is to see evil in the remedy, and to complain precisely of what tends to make the confusion cease.”

Thus he concluded that “the error of the organic school [Saint-Simonians] is the belief that liberty is only a provisional utility…. It is … in the nature of things that liberty of examination will be perpetually necessary. Society which lives chiefly by action, acts, at each instant, according to the notions that it possesses, but, to act better and better, it needs to work constantly to perfect its knowledge, and it is only able to succeed by means of liberty: research, inquiry, examination, discussion, controversy, such is its natural state, and such it will always be, even when its knowledge has acquired the greatest certainty and understanding.”

In pursuit of this life-enhancing knowledge the political program based on liberal cosmopolitanism — libertarianism — centers on unconditional free trade and freedom of movement, that is, open borders for people, capital, producer goods, and consumer goods. This program represents not merely an adherence to an abstraction, liberty. Rather it embodies the understanding that the flourishing of flesh-and-blood individual human beings, like the division of labor, is limited by the extent of society and that therefore the boundaries of society should be expanded through peaceful voluntary exchange to include the entire world. Trump’s and Bannon’s nationalist, tribalist program is thus exposed as a threat to human flourishing.