America is not post-Christian, or secular or pagan, as too many allege, Douthat insists. Christianity remains the overwhelming "controlling influence," and Americans are as religious, or more so, than ever. But with traditional churches weakened, they are also increasingly heretical in their faith understanding. Americans have traditionally reinvented their religion, he readily admits.

"We've always been a nation of heretics but they didn't have the field to themselves," Douthat observed. The "shocking" collapse of once dominant Mainline Protestantism has especially left American religion divorced from institutional guidance. Growing evangelical churches have not been sufficient to fill the cultural and spiritual void.

Thanks to neo-orthodoxy, Mainline Protestantism did recover from early 20th century liberalism in America's post World War II revival, Douthat recalled. Catholicism also left its ethnic ghettos in the 1940s and 1950s to become a forceful public voice. Joined by previously marginalized black churches, American Christianity across two decades achieved a "convergence" that the 1960s shattered.

Douthat faults the Sexual Revolution, Mainline Protestantism's slide into far left politics, divisions within Catholicism, and surging American affluence, which challenged traditional Christian notions of ascetic self-denial. The popular new heresies are prosperity Gospels, self-actualized faith in the "God within," and American nationalism. Leftist Christian nationalists still believe in building a New Jerusalem in America through political power. Conservatives believe America's Founders created the perfect kingdom that liberalism has despoiled. Douthat acknowledges he's pessimistic about orthodox Christian revival. Previous revivals in America had stronger institutional churches. Non-denominational Christianity, buffeted by an increasingly hostile surrounding culture, may not have the stamina for launching a come-back.

In his response to Douthat at the National Press Club, former George W. Bush presidential speechwriter Michael Gerson hailed Douthat's book for uniquely espousing Christian orthodoxy and even concluding with an altar call, while still likely becoming a New York Times best seller. But Gerson suggested at times it lacked "charity" towards its targets. He defended evangelical Christianity, especially Pentecostalism, which is the fastest growing segment of global Christianity. And he warned against romanticizing poverty while critiquing prosperity gospels. Millions of evangelical Third World poor are not necessarily wrong to expect that reformed living may rescue them from squalor.

Gerson also complained that Douthat unfairly accused President George W. Bush of a "divisive public piety," while also labeling the Iraq War as "messianic nationalism," which Gerson called "nonsense." That war was a "prudential calculation" about removing a mass murderer, Gerson countered. He also defended evangelicals from Douthat's charges of tacky church architecture, absence of liturgy, and a talent deficit in literature. Evangelicals faithfully worshipping in school gymnasiums may leave few marks of high culture but their faith has eternal consequence. Gerson smilingly surmised Douthat envisions an ideal church full of artistically sensitive, intellectual sophisticates. "I'd like to visit that church but I'm not sure it would have a large congregation," Gerson concluded.

Douthat accepted Gerson's critique graciously, acknowledging his own perspective is Catholic and not evangelical. While celebrating the rapprochement between American orthodox Protestants and Catholics, he surmised: "It's important for Catholics to be Catholic and Protestants to be Protestant." Gerson agreed with Douthat's premise that politicized faith can be damaging. But he hailed evangelical/Catholic cooperation as a cultural "camaraderie of the fox hole" that is "one of the best things to happen in American religion."

Despite his professed pessimism about American Christianity, Douthat riposted, "Our faith is dependent on unexpected resurrections." In its earliest centuries, thriving Christianity was countercultural. It may yet again sufficiently resurrect to transform American culture.

Douthat's sanguine view on the future of America and its faith is itself deeply in keeping with American Christianity. Nearly every generation of American revivalists across four centuries has warned its contemporaries against spiritual laxity and impending demise. And almost all American Protestant revivals have emerged as a reaction against religious institutions, not because of them. Meanwhile, liberal Catholicism seems to be ebbing, though Douthat warned against the proclivity of some conservative Catholics to assume they're a faithful remnant within the church.

Somewhat in keeping with the late Richard John Neuhaus, who insisted America remained exasperatingly Christian despite all evidence to the contrary, Douthat's underlying theme is still hopeful. America's "heretics" are still clinging fretfully to Christianity. And sometimes heretics later become saints.

Mark Tooley is president of the Institute on Religion and Democracy in Washington, D.C. and author of Methodism and Politics in the Twentieth Century