In October 1938, James Fifield of the First Congregational Church in Los Angeles sent a missive to 70,000 religious leaders across the country. His request was unusual: to rally them in opposition to recent developments in Washington, D.C. “We ministers have special opportunities and special responsibilities in these critical days,” the letter opened. The country, Fifield warned, was headed down the path toward dictatorship, and religious men of the nation had the burden of protecting the “sacredness of individual personalities”—a commitment they shared with the son of God—against the depredations of Franklin D. Roosevelt: “We may be called unpatriotic and accused of ‘selling out,’ but so was Jesus.”

Not long before writing his letter, Fifield had helped found a group called Spiritual Mobilization, which took as its founding position the idea that ministers had an obligation to check the trend toward “pagan stateism” [sic] represented by the New Deal. Throughout the 1940s and 1950s, Spiritual Mobilization sought to rally clergymen to fight liberalism, arguing that the only political position compatible with Christianity was laissez-faire. They aimed to counter the ideas—summed up as the Social Gospel—that good Christians might have obligations to help the poor, that there was something spiritually problematic about the love of money, and that working to create a better and more egalitarian social order might be necessary to live a righteous life. In his first inaugural address, Roosevelt had celebrated the expulsion of the money changers from the “temple of our civilization,” and called for replacing the “mad chase of evanescent profits” with a return to more noble social values. Spiritual Mobilization begged to differ, insisting instead that profit could be the cornerstone of a moral vision.

The group was backed financially by conservative businessmen—such as J. Howard Pew, the president of Sun Oil, and Charles White, the president of Republic Steel—and many corporations, including General Motors, Gulf Oil, International Harvester, and Chrysler, all drawn to the group’s strident opposition to the Social Gospel. Among the most prominent efforts of Spiritual Mobilization was its attempt in 1951 to mobilize a vast campaign on the theme of “Freedom Under God,” which made the case that the “root cause” of the malaise afflicting postwar America was the “disintegration of the nation’s spiritual foundations.” Fifield himself had much in common with the industrialists whose funding he received. He rejected biblical fundamentalism and described reading the Bible as “like eating fish—we take the bones out to enjoy the meat.” He lived in a lavish mansion appointed with a butler, ministered to a blue-chip congregation that included various prominent industrialists and the filmmaker Cecil B. DeMille, and embraced his identity as a man who preached to the rich: “I have smiled when critics of mine have called me the Thirteenth Apostle of Big Business or the St. Paul of the Prosperous.”

In One Nation Under God, Kevin M. Kruse, a historian at Princeton, brings Fifield to life, along with a host of other odd characters from the nearly forgotten Christian libertarian movement of the 1950s—a mobilization that, far from being on the fringes, managed to transform the relationship between church and state in America during the Eisenhower years. In so doing, he revises many deep assumptions about the nature of the modern Christian right and the role of religion in American politics.

Prior to the 1950s, Kruse suggests, religion may have been important, but it was also largely separate from the state. Only under Eisenhower did paper currency begin to bear the words “In God We Trust,” while the Pledge of Allegiance was revised to include an explicit reference to God. These everyday invocations of faith were not the result of an innate religiosity, the reflections of a culture that has always embraced the church. Rather, they reflect the specific politics of the post-New Deal era, and the effort to shore up Christian commitments to capitalism as opposed to the welfare state. Today, as Christian conservatives seem to be reeling from the “setback” of the Supreme Court decision on gay marriage, with some even discussing a retreat from the public sphere, it’s worth remembering that at least part of the religious right has always been concerned as much with the minimum wage and taxation as it has with family and sexual politics. Ironically, when contemporary Christian conservatives insist that we have fallen away from a more pious society, the golden age they point to was in fact the invention of people like Fifield—hardly biblical fundamentalists, and whose faith was always more about the market than the cross.

When Alexis de Tocqueville visited America in the 1830s, one of the aspects that most struck him about the young nation was the centrality of Christianity to its political culture: “The Americans combine the notions of Christianity and of liberty so intimately in their minds, that it is impossible to make them conceive the one without the other; and with them this conviction does not spring from that barren traditionary faith which seems to vegetate in the soul rather than to live.” It was, after all, the time of the Second Great Awakening, which saw the spread of a passionate brand of evangelical Christianity across the country. Ever since de Tocqueville’s day, the intensity of religiosity in America, and its intertwining with the country’s political sentiments, have come to be taken as a matter of faith itself, a political truism accepted by many on the right and left alike. Religion seems like a basic aspect of American political culture, something so non-negotiable and fundamental that it’s hard to imagine that it could have ever occupied a less central place than it does today.

From this perspective, One Nation Under God comes as something of a revelation (pardon the expression). Kruse makes the case that whatever the relationship between faith and the state in the nineteenth and early twentieth centuries, that connection went through a profound transformation in the 1950s. Not even the Civil War (another high point for politicized religion) saw religious ritual become so entwined with governance. What is especially striking about this shift is that it happened through a set of campaigns that were explicitly intended to increase the role of religion in politics. The first organizers of this effort were conservative activists such as Fifield, who were drawn to the cause not out of a desire to set the United States apart from the godless Soviets, as is often thought, but because they wanted to rally opposition to the New Deal, organized labor, and the ideals of the welfare state.

Kruse’s book (of which I saw a couple of chapters in draft form) is primarily about the 1950s, but its argument has implications for how we think about Christian conservatism today. Typically, historians and others have treated the rise of the Christian right as a development of the 1970s, a backlash against the changing sexual and familial mores of the time—especially the legalization of abortion, the rise of feminism, and the spread of the gay rights movement. Christian conservative leaders used churches to mobilize voters and turn them out to support candidates who would back “family values.” In the process, they politicized religion to a degree never imagined before.

Kruse turns this argument on its head. He asserts that long before the 1970s, religious leaders such as Fifield and the businessmen who backed them sought to politicize the country’s churches, seeing them as a natural and sympathetic base. Their concern was not social or sexual politics, but rather economics—they wanted to advance a libertarian agenda to undermine the economic program that became ascendant during the New Deal. This top-down Christianity in turn provided an image of the United States as an explicitly religious nation, creating a rhetoric that inspired the populist Christian conservatives of a later generation. When the men who built the religious right in the 1970s—such as Jerry Falwell and his Moral Majority—issued their jeremiads about the United States as a fallen nation, they made the implicit case that the country had hewed more closely to faith before the 1960s. But in fact, Kruse suggests, the pumped-up image of America as a Christian nation had gained popularity only a decade before.

One Nation Under God is not really a history of Christian conservatism, nor is it a book about theology or a social history of religion. Instead, it is a history of the public dimensions of faith, the performance of piety in the public sphere, and the explicit efforts to marry the idea of the United States to a Christianity the most salient feature of which was its fervent embrace of individualism.

Some of the activists Kruse chronicles, like evangelist Billy Graham, are better known than Fifield, but Kruse presents them in a new context. Although Graham is often seen primarily as a Cold Warrior, one of his major concerns at the outset of his public career was really the encroachment of the liberal state—not surprising, since one of his strongest financial supporters was oilman Sid Richardson, one of the wealthiest men in the nation at the time. Graham opposed the Marshall Plan and the welfare state, and attacked the Truman Administration for spending too much on each. He delivered a sermon in 1951 that painted a picture of the “vultures” circling “our debt-ridden inflationary economy with its fifteen-year record of deficit finance,” about to close in for “the kill.” That same year, Graham warned the audience at a North Carolina crusade that the country was no longer “devoted to the individualism that made America great,” and that it needed to return to the “rugged individualism that Christ brought” to humankind. He and Fifield were joined in their efforts by Abraham Vereide, a Methodist minister who started prayer breakfasts of local elites in cities across the country, ultimately taking his efforts to Washington, D.C., to start the National Prayer Breakfast—a tradition continued today by Democrats and Republicans alike. Both Graham and Vereide (and Spiritual Mobilization) lent their support to the 1952 presidential campaign of Dwight D. Eisenhower, the man who would—according to Kruse—do the most of any modern President to fuse capitalism, Christianity, and the national government.

Eisenhower embraced religion with enthusiasm, although in Kruse’s portrayal he seems to have liked the idea of encouraging religiosity as much as he felt passionately religious himself. While on the campaign trail, he described his bid for the presidency as a “great crusade for freedom.” He met often with Graham for spiritual inspiration. His inauguration had heavy religious overtones: He invited his entire Cabinet to a special worship service and led the nation in a televised prayer. Shortly after he was elected President, Eisenhower gave a famous speech for the Freedoms Foundation (an organization packed with executives committed to the cause of Christian libertarianism) at the Waldorf-Astoria in which he asserted, “Our form of government has no sense unless it is founded in a deeply felt religious faith, and I don’t care what it is.” Eisenhower did all he could to bring his brand of piety into the White House. He insisted on opening all his Cabinet meetings with prayer. While he was in office, the phrase “under God” (borrowed, perhaps, from the Spiritual Mobilization campaign) was incorporated into the Pledge of Allegiance and the words “In God We Trust” were printed on the nation’s currency. There was minimal debate about the matter: When the House Committee on Banking and Currency discussed it, there was one lone dissenter—a Jewish representative from Brooklyn, who noted, somewhat weakly, “If we are going to have religious concepts—and I am in favor of them—I don’t think the place to put them is on our currency or on our coins.”

What comes across most strongly in Kruse’s account is the strange political and religious style of what he dubs Christian libertarianism—which was remarkably vague as to the specifics of denomination or creed, but deeply confident that Christianity could be a potent tool in the fight against collectivism. Kruse tells the stories of the many “pitchmen” of the 1950s who argued that Christianity was the answer to liberalism, socialism, and the Soviet Union. They ranged from Walt Disney, who wanted to include an exhibit re-creating a colonial town titled “One Nation Under God” in an addition to his theme park (the plans were never fully realized), to Cecil B. DeMille, whose Hollywood pageants were part of a broader campaign for right-to-work laws and against union security. As DeMille’s participation suggests, these were not fringe figures: The J. Walter Thompson Company, then the largest advertising firm in the world, ran a massive campaign on behalf the Advertising Council to urge church (and synagogue) attendance. Some would have gone much further than the Pledge of Allegiance: Senator Ralph Flanders of Vermont—a “fundamentalist on free enterprise,” according to one Saturday Evening Post profile—pushed for a constitutional amendment that would have pronounced, “This Nation devoutly recognizes the authority and law of Jesus Christ, Saviour and Ruler of nations[,] through whom are bestowed the blessings of Almighty God.”

Not everyone agreed about the blessings of what Kruse refers to as “religious nationalism.” In 1962, the Supreme Court struck down state-mandated prayers in public schools, deeming them a breach of the separation between church and state. Such prayers had become more common since the 1950s. The New York Board of Regents, for example, had passed a statement in 1951 declaring that “[b]elief in and dependence upon Almighty God was the very cornerstone upon which our Founding Fathers buil[t],” recommending that each school day should begin with a prayer: “Almighty God, we acknowledge our dependence upon Thee, and we beg Thy blessings upon us, our parents, our teachers, and our Country.” It was shocking when the Court ruled that such prayers were unconstitutional. Confident in their belief that the United States had been a Christian nation throughout its history, hundreds of letter-writers deluged Justice Hugo Black (the author of the decision) with objections to his opinion. “When do you plan to require our Government to take ‘IN GOD WE TRUST’ off our money?” asked one Virginian, perhaps unaware of just how recently it had been added on.

The self-conscious faith of the Eisenhower years became the object of nostalgia during the Nixon presidency. As the country was divided over the Vietnam War and the civil-rights movement, conservative political leaders began to invoke the 1950s as an era of unity by comparison. Nixon held worship services on Sundays in the East Room of the White House, inviting a different religious leader each week to address the President, his wife, and Cabinet members. For Nixon, such maneuverings were clearly opportunistic: “Sure, we used the prayer breakfasts and church services and all that for political ends,” his aide Charles Colson later said. Graham was the first to speak at the White House, and Nixon then went to address Graham’s revival meetings. Still, the new Christian conservatives who were gaining momentum in the 1970s looked back to the 1950s as a time of great public piety. By creating the first wave of Christian conservatism in the 1950s, the right wing of that era had established a standard that the latter-day conservatives could extol as the norm.

One Nation Under God is an impressively researched work of history. The depth of Kruse’s archival scholarship—the bibliography lists 64 manuscript collections—is especially vital given the potential sensationalism of his topic. Yet sometimes one wishes that Kruse had gone further than he does in tracing the legacy of Christian libertarianism and taking his story up to the present time.

At first glance, the movement he chronicles may seem like it hails from a very different period in the history of the right. Today’s religious conservatives seem—as they have for the past 40 years—to be preoccupied above all with social issues: abortion, feminism, same-sex marriage. Contemporary libertarians, by contrast, have sought to separate themselves from the religious right in an effort to win the support of people who are alienated by the culture wars. The Republican candidates for 2016 seem to take the Baskin-Robbins approach to politics, offering every flavor of conservatism, and much coverage of the race for the GOP nomination has reflected this sense of multiple schisms. It’s therefore fascinating to have this portrayal of an earlier moment in the history of the right, to remember a time when at least some activists made the case that good Christian leaders should take as their highest duty opposing the welfare state. It’s a reminder that there have always been Scott Walkers among the Christians, politicians whose main commitments are to fighting unions and cutting taxes, even as they seek to shore up the support of a religious base.

Kruse’s book also points to the creation of a set of norms around religion that now transcend political party—“invented traditions,” to use historian Eric Hobsbawm’s phrase, that hold as much power as they would have if they had existed since time immemorial. The apparatus of official religion has been adopted as thoroughly and unquestioningly by the Democrats as the Republicans, and it seems almost impossible to imagine a President who would cancel the White House Prayer Breakfasts or decline to invoke the Almighty in a State of the Union address.

Christian conservatism exists in an odd dialectic with this official religiosity. No matter how empty the symbolism of the national motto may appear, the simple fact that it exists (“In God We Trust”) grants legitimacy to the notion that the United States should aspire to some kind of religious ideal. No matter how mainstream and ecumenical the National Prayer Breakfasts may seem, the simple fact that they are held and attended by the President each year gives credence to the role of the church in politics. Were we to insist on a more forceful separation of church and state, as prevailed prior to the 1950s, it would be much harder for the Christian right to make the claim that the country is failing to fulfill its ideals and traditions. Instead, these rituals would come to be seen as what they truly are: relics of the cultural conflict that roiled the country in the wake of the Great Depression and the New Deal, a conflict that reshaped American politics in ways we are still living with today.