At first glance, Robert Kagan’s Rebellion is an answer to the growing library of books, essays, and social-media content associated with the “New Right.” These works reject the post–Cold War international order. Kagan defends it. They question whether modern America is the rightful heir of the Founding. Kagan draws a straight line from 1776 to the present. They support Donald Trump, at least instrumentally. Kagan denounces Trump as the most profound threat to the republic since the Civil War.

Where Rebellion diverges from the intellectual output of the New Right, though, is less interesting than what it shares with that literature. One common feature is a rhetoric of existential crisis. American institutions, Kagan insists, are not merely strained. Without dramatic intervention, they may not survive the next few years.

A second point of agreement lies in the historical narratives that lead up to the present crisis. These are not stories of specific persons making difficult decisions under challenging circumstances, with unpredictable and often unsatisfactory results. They are clashes of big and essentially unchanging ideas conducted over a period of centuries.

This tendency toward abstraction leads to a third area of similarity: a binary contrast between the forces of virtue and the army of vice. There is no serious consideration of stated grievances, little weighing of trade-offs to determine the lesser evil, no concession that decent people might come to different conclusions. There is only a contest between the supporters of truth, justice, and human flourishing and their enemies.

With so much overlap, what’s the difference between the rival genres of “resistance” literature? It amounts to this: For the New Right, liberalism is the main source of corruption and danger in American life. If it can’t be wholly eliminated, the goal is to marginalize and exclude it as much as possible. Kagan retains the structure of the argument but reverses the valuation. For him, everything good in America is liberal. It must therefore be defended from “anti-liberalism” derived mainly from southern slave-owners.

Even for an author who specializes in sweeping generalizations (remember “Americans are from Mars and Europeans are from Venus”?), this is reductive, inflammatory, and counterproductive. The problems begin with his account of liberalism.

As with other ideologies, the meaning of liberalism is seriously contested. Kagan adopts a particularly strict definition: a commitment to protect the rights of all individuals against both legal and social restrictions. Government, on this view, has no essential connection to public deliberation, the pursuit of common goods, or the cultivation of morality. It is — or at least ought to be — simply a “machine for protecting rights.”

Kagan claims that this view is the basis of a historically extended tradition. But who actually accepted it? Probably not John Locke, whom Kagan depicts as its philosophical father. Locke famously appealed to inherent rights. But he also argued that these rights are morally constrained by the law of nature.

The status of Locke’s law of nature is somewhat obscure, and some interpreters argue that it’s no more than a veil for hedonism. When it comes to life within civil society, though, Locke rejected claims that individual freedom trumps the will of democratic majorities, defended executive prerogative in pursuit of the common good, proposed to ban atheists and implicitly Catholics, and defended a social hierarchy with propertied gentlemen at its apex.

Kagan admits that few Americans at the time of independence were liberals in his sense. He appeals broadly to “the founders.” But his evidence is drawn almost entirely from Jefferson, with cameo appearances by James Madison and Thomas Paine. New Right authors deplore Jefferson and struggle to extricate the American political tradition from his influence. Kagan makes the opposite mistake of deriving the meaning of America from inside Jefferson’s brain.

Whatever Jefferson believed, in any case, “liberalism” is not the sole theme of the Founding documents. Kagan relies on the famous second paragraph of the Declaration of Independence. He does not mention that the bulk of its text is concerned with British interference in collective self-government — not with violations of individual rights.

The Constitution is even less plausible as an expression of Kagan’s liberalism. It constrains government in important ways. Yet the unamended text makes no mention of rights and cites securing the “blessings of liberty” as only one among several purposes of government. The Bill of Rights goes farther in carving out zones of protection from interference by the national government. Still, even these amendments don’t explicitly assert enforceable individual freedoms, an idea that became common only in the 20th century.

That’s not to say that Kagan is wrong to see something liberal about the Founding. Contrary to claims that it emerged decades later and in Europe, the term “liberal” was already being used in Anglophone contexts in the 18th century. But it was originally used as an adjective rather than an ideological “-ism.” In politics, it was associated with popular sovereignty, a commercial economy, and citizens’ equality before the law. Because of its acceptance of these principles, the emerging American regime is reasonably described as a liberal republic. Yet it was not merely a machine for protecting rights.

Secondary to the Founding itself, emphasis on the indefeasible character of individual rights dates from a later period. For all its virtues, the liberal republicanism of the Constitution had no serious way of dealing with slavery, which proved more profitable and durable than most Founders sincerely if conveniently expected. Opponents of slavery embraced the natural-rights passage of the Declaration because it provided a criterion that transcended both the legal strictures of the Constitution and the informal standards of custom. The pivotal figure in Kagan’s account of liberalism is not Locke or even Jefferson. It is Lincoln.

Here again, Kagan could make a serious point against some of his opponents. Whatever early Americans thought or hoped, a stronger theory of rights proved necessary to establish an acceptable degree of justice. But Kagan is not content with this limited victory. Instead, he reinterprets American history as an irrepressible conflict between high-proof liberalism and systematic anti-liberalism.

Such essentialism would be merely annoying if it were an argument about the long-ago past. What makes Rebellion preposterous and even pernicious is that it projects the conflict over slavery forward into the present. In Kagan’s telling, every major dispute since 1865 has been an echo of the Civil War. For Kagan, it’s not just supporters of Jim Crow who were heirs to the Old South. Critics of large-scale immigration, opponents of foreign wars, and originalists in constitutional interpretation (among others) are all depicted as “anti-liberal” for much the same reasons and in much the same way as the ideologues of the Confederacy.

The incoherence of this interpretation is evident in Kagan’s attack on the modern Right. His initial definition of liberalism sounds almost libertarian in its emphasis on the limits of governmental and social power. When he considers the deployment of such arguments against the New Deal and its legacy, however, Kagan dismisses them as little more than masks for white supremacy. His accusation of underlying racism extends to the founders of this magazine, whom he blames for the ostensibly anti-liberal character of the post-war conservative movement. He does not venture to explain their enthusiasm for Barry Goldwater, whose views came closer to philosophical liberalism as Kagan describes it than have those of any other presidential candidate since World War II.

To be fair, Kagan does not see racism as the only source of American anti-liberalism. He also worries about a so-called Christian nationalism that seeks to commit American institutions to theological purposes. Kagan not only endorses the theory, notionally derived from Jefferson and Madison, of strict separation between religion and public life; he contends that it lies at the heart of liberalism and therefore of the American order.

Once again, this is nonsense. As Kagan admits, his liberal heroes — Jefferson, Madison, and Paine — were outliers in their skepticism. Most Americans believed in the necessity of religion to a successful republic. And they largely accepted a variety of institutional measures, ranging from public prayer and official chaplains to state-level established churches, to promote that goal.

Acceptance of cooperation, if not identity, between religious and political institutions was not unanimous, and criticism was not limited to Enlightenment-minded intellectuals. Jefferson and Madison famously appealed to Baptists against Episcopalians and other Christians who favored direct support for denominational activities. But the idea that government should not favor religion in any respect did not emerge until late in the 19th century. Ironically, the argument was popularized not so much by principled secularists as by Protestants who used it against public funding for Catholic schools.

The adoption of secularism as a tool of religious discrimination shows why it is such a mistake to make liberalism the sole category of analysis. Kagan’s dichotomy does not account for the use of liberal means to achieve non-liberal ends — or vice versa.

Kagan particularly struggles to explain how figures and movements could be liberal on some issues but illiberal or even anti-liberal on others. Religious liberalism verging on secularism was more influential among slave-owning grandees, including Jefferson and Madison, than among New England moralists, who tended to oppose slavery. Rather than address these complexities, Kagan concentrates on the likes of Robert Lewis Dabney, the southern Presbyterian who defended slavery on biblical grounds. Eventually repudiated by their denominations, Dabney and other illiberal theologians have enjoyed something of a revival in online circles — partly as symbols of transgression. It strains credulity, however, to claim that they enjoy broad influence.

And it is broad influence that Kagan wants to document. Rebellion is not about provocative intellectuals, social-media influencers, or even organized ideological movements. The book opens with the extraordinary claim that “half the country does not believe in the core principles that undergird the American system of government.” He apparently means by this everyone who plans to vote for Donald Trump — or perhaps those who support any Republican whatsoever. These millions of fellow citizens, Kagan contends, are not simply confused, misguided, or insufficiently attentive to the fate of the nation. They are traitors who presumably deserve to be rejected, punished, and expunged from national life.

It’s in this respect that Kagan’s liberalism reveals its fundamental similarity to the anti-liberalism that he deplores. Rather than accepting and seeking to manage inevitable differences of opinion, interests, and ways of life, it is a rigid, exclusive doctrine that must often be imposed on implacable foes. The greatest anti-liberals have at least been honest about the polemical implications of their theories. Kagan does not appear to realize that he is extending to domestic issues the martial conception of politics that he previously applied to international affairs. What follows is the same in both cases: war.

By way of contrast, consider Lincoln’s response to an unquestionable insurrection over actual slavery. In his first inaugural, Lincoln insists:

We are not enemies, but friends. We must not be enemies. Though passion may have strained it must not break our bonds of affection. The mystic chords of memory, stretching from every battlefield and patriot grave to every living heart and hearthstone all over this broad land, will yet swell the chorus of the Union, when again touched, as surely they will be, by the better angels of our nature.

For all his commitment to the sanctity of individual rights, Lincoln also expressed hope for reconciliation, generosity toward adversaries, and an understanding of the complexity of the American story that is utterly lacking in Kagan’s account. Lincoln failed to prevent rebellion and led a bloody struggle to suppress it but also laid the foundation for eventual peace. If the liberal characteristics of the American republic are indeed threatened, it is precisely this kind of “liberalism” that we need.