A handful of Weimar émigrés left an outsize imprint on the American right. Photo Illustration by Erik Carter

A distrust of high theory used to be a mainstay of conservatism. Edmund Burke, scrutinizing support for the French Revolution, had seen connections with sinister “literary caballers, and intriguing philosophers, with political theologians and theological politicians.” Even in the middle of the past century, when American intellectuals on the right were publishing the books that buttressed a movement—Peter Viereck’s “Conservatism Revisited” (1949), Whittaker Chambers’s “Witness” (1952), and Russell Kirk’s “The Conservative Mind” (1953)—a shared aversion to grand philosophizing was palpable. What was needed, Viereck wrote, was a “revolt against ideology” and a defense of what Kirk called “permanent things,” to offset, if possible, drastic changes, whether wrought in the blood of the Russian Revolution or, as Chambers wrote of the New Deal, in “a revolution by bookkeeping and lawmaking.” Conservatives wanted, above all, to conserve. “The American political mind has never thought much along consciously radical lines,” the political scientist Clinton Rossiter wrote, in “Conservatism in America” (1955).

Yet, at more or less the moment Rossiter wrote this, some on the right were making a different case, more strident and aggressive, and unafraid of world-historical theories. In the first issue of National Review, published in November, 1955, William F. Buckley, Jr., and his fellow-editors, several of them ex-Communists, announced that they were “radical conservatives” and vowed “to stand athwart history, yelling Stop.” Like more traditional conservatives, they looked back to a better time, but not in tones of gentle pining. They conveyed instead “strangely exhilarating despair,” as the intellectual historian Mark Lilla writes in his new book, “The Shipwrecked Mind” (New York Review Books), a collection of essays on philosophical and religious reaction. “The militancy of his nostalgia is what makes the reactionary a distinctly modern figure, not a traditional one,” he adds.

Lilla, a professor of the humanities at Columbia, skillfully untangles the apocalyptic “mytho-histories,” “just-so narratives,” and “political bedtime stories” favored by the modern right, in Europe and America. For him “reactionary” is not an insult. It is a taxonomic term. It describes an organic response to political and social revolution, and the quite sensible fear that the shared common life of a people has been wrenched out of its cherished patterns. Nor is the phenomenon limited to the ideological right. The left has reactionaries, too—including progressives in the nineteen-nineties who, Lilla wrote at the time, were convinced that Americans did not grasp the disastrous truth about the Reagan Revolution, “since if they did, they would overturn it.” But reactionaries on the right far outnumber those on the left. “The enduring vitality of the reactionary spirit even in the absence of a revolutionary political program,” he writes, arises from the feeling that “to live a modern life anywhere in the world today, subject to perpetual social and technological changes, is to experience the psychological equivalent of permanent revolution.”

In the six decades since Buckley and company took their stand, conservatives still speak the same militant language. We’re just more used to it now. “All this damage that he’s done to America is deliberate,” Marco Rubio, as a Presidential candidate, said of Obama, which sounds almost like an accusation of treason. The G.O.P. warns that, as President, Hillary Clinton, despite her long record as a moderate-to-slightly-left Democrat, would try to lead us down the road to socialist perdition. Where do these passions come from? Lilla’s answer is bracingly direct. They come from the place that conservatives themselves often point to as the root of all ideological evil: Europe.

The best pages in “The Shipwrecked Mind” are elegant, concise portraits of refugees from Weimar Europe who fled to America after the Nazi takeover and brought with them “some very large and very dark ideas about the crisis of the age.” These ideas reached maturity in the first years of the Cold War. We often think of the nineteen-fifties as the decade of complacent conformism: a robust economy, a beloved war hero in the White House, slow but important progress on civil rights. But it was also “High Noon,” the doomsday thermonuclear clock ticking loudly even as a dangerous storm was brewing abroad: anti-American governments in Asia, Africa, and the Middle East, ungrateful semi-socialist regimes in Europe living under the protection of our troops and dollars, Soviet leaps in missile and aerospace technology, and a shooting war in Korea. There were even overtones of Weimar “stab in the back” conspiracy lore in Senator Joseph McCarthy’s accusation that Democrats were guilty of “twenty years of treason.”

In most accounts of the period, including Mark Greif’s recent book “The Age of the Crisis of Man” (2015), the dominant refugee is Hannah Arendt, whose “Origins of Totalitarianism” (1951) depicted the rise of Hitlerism and Stalinism as twin modernities, engines of mass terror built to effect “the transformation of human nature itself.” Its blend of history, philosophy, and intellectual drama—a postwar addendum to Spengler’s “The Decline of the West”—was keyed to the mood of chastened leftists. But conservatives had their own pantheon of foreign-born exotics, who dispensed very different lessons and left a deeper and more lasting imprint on our politics.

Friedrich Hayek’s “The Road to Serfdom,” a potent critique of centralized government planning, was a best-seller in 1944 (and again in 2010, at the zenith of the Tea Party revolt). His mentor Ludwig von Mises, dean of the Austrian School of economics, gave the N.Y.U. seminars—extensions of the celebrated “private” seminars he had convened in prewar Vienna—that planted the seeds of the libertarian movement still flourishing today. And the Russian émigrée Ayn Rand and her young “collective,” including Alan Greenspan, gathered at her Murray Hill apartment on Saturday nights to hear fresh pages of her novel in progress, “Atlas Shrugged.” (It remains a sacred text on the American right, a favorite of Paul Ryan, although Gary Johnson prefers her previous novel, “The Fountainhead,” and Rand Paul “cut his teeth” on her entire œuvre.)

Lilla enlarges and subtilizes the picture by working through the legacies of two other refugees, the political philosophers Eric Voegelin and Leo Strauss. Voegelin was born in Cologne but grew up in Vienna and, in the nineteen-twenties, spent two years in America, where he heard John Dewey lecture at Columbia. He returned to Vienna to teach. (He also attended Mises’s private seminars there.) When Hitler rose to power, Voegelin bravely published an attack on biological racism. After the Anschluss, he escaped by train to Switzerland while Gestapo agents were searching his apartment. In America, he bounced from Harvard and Bennington to Northwestern and Alabama, before finding a longer-term berth at Louisiana State University.

In the fifties, he wrote a backward-looking prophecy that had a Vico-like sweep and title, “The New Science of Politics.” Its argument was elegant and powerful. The decline of the West had its origins in the early days of Christianity, “the first world religion to offer theological principles for distinguishing divine and political orders.” It filled men with thoughts of divinity, but its promise of final deliverance, or “eschaton,” bred impatient dreams of secular cities of God, built here and now. Voegelin, who had a weakness for odd coinages, called this “the fallacious immanentization of the Christian eschaton”—Heaven on earth, achieved through “political religion.”