Once, the iconic figures on the political right were urbane visionaries and builders of institutions — like William F. Buckley Jr., Irving Kristol and Father Richard John Neuhaus, all dead now. Today, far more representative is potty-mouthed Internet entrepreneur Andrew Breitbart, whose news and opinion website, Breitbart.com, is read by millions. In his most recent triumph, Breitbart got a U.S. Department of Agriculture official pushed out of her job after he released a deceptively edited video clip of her supposedly endorsing racism against white people.

What has become of conservatism? We have reached a point at which nothing could be more important than to stop and recall what brought us here, to the right, in the first place.

Buckley’s National Review, where I was the literary editor through the 1990s, remains as vital and interesting as ever. But more characteristic of conservative leadership are figures on TV, radio and the Internet who make their money by stirring fears and resentments. With its descent to baiting blacks, Mexicans and Muslims, its accommodation of conspiracy theories and an increasing nastiness and vulgarity, the conservative movement has undergone a shift toward demagoguery and hucksterism. Once the talk was of “neocons” versus “paleocons.” Now we observe the rule of the crazy-cons.

When I was a college student in the late 1980s interviewing for an internship at National Review, Managing Editor Richard Brookhiser fixed me with a look and posed a question that might seem more natural in a religious than in a political context. “How did you become a conservative?” he asked.

Evangelical Christians, curious about their fellow believers, will sometimes ask something similar: “How did you become a Christian?” Among conservatives, most of us too had “born again” stories, but they were political rather than religious. (Though sometimes our philosophical paths led to new religious paths as well: The first step on my own journey to Orthodox Judaism was to become a conservative.)

Conservatism wasn’t just a policy agenda, a set of partisan gripes or a football team seeking victory on the electoral field. Above all, it was a satisfying, sophisticated critique of modern, materialist culture, pointing a way out and up from liberalism.

Defining conservatism is notoriously difficult. But no one did it better than philosopher Richard M. Weaver in a book that, more than any other, launched the modern conservative movement. Published in 1948, the book was “Ideas Have Consequences.”

Weaver compared his role to a doctor diagnosing an illness. It is not enough to want to treat the symptoms — in this case, of our demoralized, dispirited culture. You must understand the genesis of the disease.

Weaver describes the course of the revolution in thought that led from a seemingly obscure philosophical debate in the Middle Ages through Darwinian evolutionary theory to class-based determinist theories in economics and onward to contemporary liberal relativism.

In the process of disintegration was an ancient, shared picture of the world and our place in it. Once, Western culture was blessed by a “metaphysical dream” that meaningfully explained man to himself as, in the phrase from Psalms, “a little lower than the angels.” Now humans were reduced to mere animals.

Weaver observed: “If we feel that creation does not express purpose, it is impossible to find an authorization for purpose in our lives.” A life without real purpose is likely to be anxious, restless, prone to bitterness and suspicion. The goal of conservatism was to restore to men and women a metaphysical dream that allows for ultimate meaning in our existence.

The idea of purpose in the cosmos was central to the conservative vision. Another icon on the right, Whittaker Chambers, described in his 1952 memoir, “Witness,” the moment he awoke from his earlier communism: It was upon looking closely one day at his young daughter’s ear. Noting the exquisite beauty, the evidence of “immense design” shook him. He could never again subscribe to the secular, materialist dream.

When I became a conservative, that is what I signed up for: a profound vision granting transcendent significance to public life and hope in private life. The goal wasn’t to defeat Democratic officeholders or humiliate left-wing activists. It was, and still is, with those who remember, to save civilization.

David Klinghoffer is a senior fellow at the Discovery Institute and the author of, among other books, “Why the Jews Rejected Jesus: The Turning Point in Western Civilization.”