The Evangelicals: The Struggle to Shape America. By Frances FitzGerald. Simon & Schuster; 740 pages; $35.

VISIT an evangelical church in America on a Sunday morning, and you are likely to be embraced, perhaps literally, by fellow worshippers, then impressed by the pastor’s scriptural exegesis. Depending on his text, and on the news, he may remind his flock that the devil walks among them, and of the risk—a perennial one for white evangelicals, as Frances FitzGerald’s timely and enlightening book makes clear—that depravity may turn God away from their country. Yet in November four out of five of these decorous, Bible-loving Christians voted for an adulterous reality-television star who has said he has never sought divine forgiveness.

White evangelicals make up around a fifth of America’s population, yet four decades after they became a central feature of public life they continue to baffle their compatriots. “The Evangelicals” was written before Donald Trump’s victory, but it illuminates these contradictions. Ms FitzGerald, a Pulitzer prizewinning historian, shows how the rise of evangelical creeds, during the Great Awakenings of the 18th and 19th centuries, was itself a sort of populist revolt, by “a folk religion characterised by disdain for authority and tradition”. It was not only anti-elitist but anti-intellectual, “a religion of the heart, as opposed to the head”, in which puritanical harangues were leavened by the promise of a widely shared salvation and, after a born-again experience, a direct relationship with God.

Spread, often, by untutored preachers using vernacular storytelling, this was an insurgent faith suited to the frontier. Today its adherents seem sceptical of religious tolerance, but initially they advocated it, so as to compete with established churches. Rival attitudes to that kind of activism—whether to withdraw from the secular world and patiently await the Rapture, or to engage in the hope of speeding it along—form one of the axes around which Ms FitzGerald’s narrative turns. The others include the tensions between the North and the evangelical heartland of the South, the argument over the fundamentalist belief in biblical inerrancy and the ongoing dispute over whether America should be a light unto the nations or an isolated refuge of piety.

Ms FitzGerald explains how, along with these internal conflicts, urbanisation, war and immigration shaped the evangelical world, just as evangelicals, “the most American of religious groups”, helped to shape the nation. She concentrates, topically, on the rise of the evangelical right. Fundamentalism, she says, seemed to have been routed at the Scopes monkey trial of 1925, when William Jennings Bryan failed to defend the Bible’s literal truth, or so many bystanders reckoned. But it recovered in the general religious boom after the second world war, energised by celebrity revivalists, above all Billy Graham, and by the dizzying social advances of the following decades, which many pastors vehemently resisted.

The presidential campaign of 1980, starring “a divorced former Hollywood actor who rarely attended church”, saw an alliance emerge between Jerry Falwell’s Moral Majority and the Republican Party; the relationship between the party and the Christian right has since wavered between passion and wariness, taking a toll on both sides. Falwell may be the book’s single most important character. He not only led white evangelicals into mainstream politics, Ms FitzGerald writes, but injected the evangelical mode of thinking with them. Waging “holy war” against secular humanism, he “introduced the fundamentalist sense of perpetual crisis, and of war between the forces of good and evil”.

Falwell is also a good example of Ms FitzGerald’s method, and its success. This is a monumental study. Some of its detail—such as the varieties of religious experience that evangelical churches encompass, from Pentecostal charismatics and snake-handlers to the prosperity gospel—is gripping. Some of the theological rows, for example over the precise sequencing of the Apocalypse and the Second Coming, may weary lay readers. But the engines of her book, as of its subject, are the lives of leaders such as Falwell. His hard-living father, Carey Falwell, once killed an employee’s cat and fed it to him as squirrel stew, and threw a drunkard into a cage with a bear.

Circuit-riding preachers, megachurch pastors, millionaire televangelists who traded on their audiences’ willingness to suspend disbelief: she sketches her characters in gory technicolour. She is droll about their chicanery and non-judgmental about their conspiracy theories, prophecies and prejudices. There are fanatics and entrepreneurs, like Pat Robertson, a broadcasting impresario who ran for president in 1988 under the half-familiar slogan, “Restore the Greatness of America Through Moral Strength”. There are charlatans who take to extreme lengths the presumption of forgiveness that is central to their faith’s structure and appeal. These are mercurial, self-invented, quintessentially American lives.

False idols

By the administration of George W. Bush, white evangelicals’ favourite president, their political agenda had narrowed. (Abortion, Ms FitzGerald notes, became a preoccupation only in the 1980s.) Partisanship intensified such that “Bill and Hillary Clinton were the Antichrist.” Many evangelicals have become wedded to a seemingly un-Christian social policy that “elevated opposition to higher taxes and [Barack] Obama’s health-care reform to the status of biblical absolutes”. The Supreme Court’s legalisation of gay marriage in 2015 was, for them, a calamity. Meanwhile, despite their egalitarian impulses, these congregations always had an authoritarian, patriarchal bent, the chain of command running from God to husbands and fathers. And so they, and America, arrived at Mr Trump.

It is a shame that Ms FitzGerald excludes black evangelical churches, with all their struggles and heroism. As she says, “theirs is a different story,” but the two are intertwined—not only in the history of slavery and segregation, both defended by the Southern Baptists, the country’s biggest Protestant denomination (and probably most outsiders’ paradigmatic evangelical church). White and black evangelicals will converge in future as well: as she observes, white congregations are greying, so that, despite the nativism rife in many, their vitality will increasingly depend on attracting black and Hispanic members.

She does examine the quieter, but burgeoning, Christian left, a movement that emerged in the 1960s, aiming to recapture the spirt of reform that marked earlier evangelical eras. Likewise she refers to the growing subset of thinkers and activists who are orthodox in theology but renounce the bankrupting compact with the Republican Party and the fixation on sexual morality. These groups, who care as much about life after birth as before it, and value justice in the sublunary world as well as salvation in the next, are evangelicals too.