It's perfectly reasonable to worry about what will happen after Britain's historic vote to break up with the European Union. Will Brexit provoke Scotland and Northern Ireland to secede from the United Kingdom, leading to its dissolution? Will it embolden other members of the EU to bolt? And will those secessionist movements empower unsavory characters who end up being seduced by Vladimir Putin and modeling themselves on his form of authoritarian populism? Will the dire short-term economic consequences of Brexit create chaos and recession in the long term, too?

As I said, lots of reasons to worry.

But what we've seen from a wide range of writers and analysts in the days since the Brexit vote is not necessarily worry. It is shock. Fury. Disgust. Despair. A faith has been shaken, illusions shattered, pieties punctured. This is what happens when a life-orienting system of belief gets smashed on the rocks of history.

The name of that shattered system of belief? Progressivism.

I used to be a conservative. I now consider myself a liberal. But I have never called myself a progressive. There's a reason why, and it has nothing to do with policy.

Liberals believe in the rule of law; in individual rights to speech, worship, assembly, and private property; in an independent judiciary and civilian control of the military; in representative institutions founded on the consent of the governed; in democratic elections, not as ends in themselves but as checks on the power of government and as a means of gauging and forging popular support for policies pursued by public officials in the name of the common good.

Progressives believe in all of that, too, but they add something else: a quasi-eschatological faith in historical progress that gives the movement its name. This belief has many sources, and it takes many forms. One stream flows from liberal Protestant theology on down through Woodrow Wilson's hopes for moral advances at home and an end to armed conflict abroad — with both of them realized by an elite class of public-spirited experts. The same theologically infused faith informs Barack Obama's frequent invocation of an "arc of history" that "bends toward justice."

A secular variation on these messianic hopes was forged by Immanuel Kant, who insisted it was a necessary "postulate of practical reason" to believe that history is moving toward the realization of "the highest good" (including a future of "perpetual peace"). G.W.F. Hegel went further, transforming Kant's essays on progress into an elaborate philosophy of history that culminated in the realization of absolute self-consciousness and freedom in the modern liberal state.

Hegel's greatest 20th-century student, Alexandre Kojève, pushed even further, to propose that mankind was on the cusp of establishing a "universal, homogeneous state" in which all of humanity's desires would be recognized and fulfilled. (Francis Fukuyama's The End of History and the Last Man was an attempt to update and apply Kojève's progressive insights to the immediate aftermath of the Cold War.)

Whether or not it's expressed in explicitly theological terms, progressivism holds out a very specific moral vision of the future. It will be a world beyond particular attachments, beyond ethnic or linguistic or racial or religious or national forms of solidarity. In their place will be the only acceptable form of solidarity: humanitarian universalism.

And this means that the progressive future will even result in the end of politics itself — at least if politics is understood as encompassing more than the jostling of interest groups, bureaucratic administration, and the management of government benefits. Politics in that narrow sense will remain. But politics in Aristotle's sense — this particular community in this place with this history and heritage, determining its own character for itself, deciding who is and who is not a citizen, who will rule, and in the name of which vision of the good life — that existential form of politics will cease to exist in the progressive future.

Politics in this expansive sense will come to an end in the imagined progressive future because there will be nothing left to debate. The big questions of politics will already be answered, the big disputes settled once and for all. Everyone will understand that all particular forms of solidarity are morally indefensible (just various forms of racism) and that all strong political stands against humanitarian universalism in the political realm are politically unacceptable (just various forms of fascism).

It would be one thing if progressives understood their universalistic moral and political convictions to constitute one legitimate partisan position among many. But they don't understand them in this way. They believe not only that their views deserve to prevail in the fullness of time, but also that they are bound to prevail.

It is this faith in the inevitability of progressive triumph that has led so many commentators to respond so intensely to the rise of Donald Trump. I don't mean reactions that focus on Trump's personal, temperamental shortcomings. Those are real and worthy of serious concern. I mean reactions that take the form of moral indignation and outrage — as if the very fact that millions of voters have cast ballots for a candidate who strongly opposes immigration and free trade is some kind of moral and theological betrayal, or an offense against capital-H History itself.

The progressive response to the outcome of the Brexit vote is remarkably similar.

It's easy to understand its sources. The European Union may well be the purest and most ambitious experiment in progressivism ever attempted — a transnational economic and political entity founded entirely on the moral premises of humanitarian universalism, which is to say on the negation of particularistic attachments. (Kojève was one of the chief planners of the European Common Market, the predecessor to the EU.)

Yes, neoliberal economic policies (as well as fiscal austerity) undoubtedly played a big role in provoking anti-EU sentiment in Great Britain. But I suspect Angela Merkel is the real catalyst behind the outcome of the UK referendum. Not only did the German chancellor insist on admitting well over a million refugees and migrants from the Greater Middle East into the heart of Europe. Supporters of the policy have also made it clear on numerous occasions that they consider racism and xenophobia to be the only possible grounds for opposing her stand.

From the standpoint of progressivism, this makes perfect sense. An open-door policy toward refugees and migrants fleeing unrest in the Levant and North Africa is obviously the only morally acceptable option. It shouldn't matter whether those immigrants are Muslims, or if they're Syrians or Libyans, skilled or unskilled, poor or middle class, literate or illiterate, eager to assimilate or convinced of the need to resist it, looking for freedom and pluralism or hoping to build an enclave of Sharia law within the West. And there's certainly no reason to suspect that any of them might turn toward terrorism, now or a generation from now. They're just placeless people — human beings in need of aid, comfort, and charity. That's all that should matter.

Except that many millions of citizens in EU member countries don't see it this way. It does matter to them, just as it also matters to them whether Turkey is eventually invited to join the union, and they don't appreciate having their concerns about the ethnic, religious, linguistic, and economic character of their political communities dismissed as moral pathologies.

In this way, Merkel's grand progressive-humanitarian gesture has backfired badly — rekindling and potentially intensifying the very nationalistic solidarity that progressives once hoped the EU would dissolve or erase.

If history is moving inexorably toward humanitarian universalism, then giving it a sharp shove forward every now and then might be necessary and even admirable. And it certainly won't meet any significant resistance. It will merely hasten the inevitable.

But what if progressivism isn't inevitable at all? What if people will always be inclined by nature to love their own — themselves, their families, their neighbors, members of their churches, their fellow citizens, their country — more than they love the placeless abstraction of "humanity"? In that case, the act of ignoring or even denigrating this love will have the effect of provoking its defensive wrath and ultimately making it stronger.

It makes perfect sense to be surprised, saddened, and concerned by the outcome of the Brexit vote. But shock? Fury? Disgust? Despair? That's what a person feels when he discovers that his most dearly held fundamental beliefs have led him astray.

Wake up, progressives! You have nothing to lose but your illusions.