Americans have been arguing about the role of religion in government since the earliest days of the republic. In 1789, soon after taking office, President George Washington declared a day of “public thanksgiving and prayer.” God had bestowed a republican government on the United States, said Washington, and the nation ought to express its gratitude. Just 12 years later, President Thomas Jefferson abruptly canceled the ritual. The First Amendment, explained Jefferson, erected a “wall of separation between church and state.”

Jefferson’s wall could have used a better contractor. Today, there is hardly an aspect of American political life untouched by religion. God seems to be everywhere. The nation’s official motto is “In God We Trust.” The phrase is printed on the nation’s money, affixed behind the Speaker’s dais in the House of Representatives, and engraved over the entrance to the Senate. The Pledge of Allegiance declares a nation “under God,” and—sorry, Jefferson—the National Day of Prayer is back (the first Thursday in May); there is even a National Prayer Breakfast (the first Thursday in February). When they address the nation, U.S. presidents almost always conclude with a request that “God bless America.”

All this religiosity isn’t exactly ecumenical: a majority of Americans consider the United States a “Christian nation.” In his fine new book, Kevin Kruse declares that, whatever the public may think today, the founders had no intention of establishing a religious (much less a Christian) republic. For the most part, they agreed with Jefferson and believed in separating church and state.

What, then, explains the religiosity of American politics? Kruse traces its origins back to the 1930s. Conservative business leaders had trouble gaining traction against the New Deal and eventually discovered that moral claims generated more popular enthusiasm than calling for free markets. The business leaders funded a national movement led by religious figures such as James Fifield, Jr., a Congregational minister who preached that the New Deal, with its emphasis on collective responsibility, had introduced a “pagan statism.” Together, these men of the world and men of the cloth engineered a spiritual revival designed to shake Americans free from creeping collectivism.

Whatever the American public may think today, the founders had no intention of establishing a religious (much less a Christian) republic.

This pro-business, anticommunist, politicized Christianity seemed to find its political champion when Dwight Eisenhower won the presidency in 1952. But Eisenhower recast the movement (Kruse implies he hijacked it) as a more ecumenical, all-American consensus that would unite the nation in the Cold War struggle against the godless Soviet Union. Eisenhower set the agenda, and Congress—Republicans and Democrats, conservatives and liberals—eagerly followed. Many of the most familiar manifestations of religion in government—the legislatively mandated allusions to God in the country’s official motto, on its money, and in its Pledge of Allegiance—emerged during the Eisenhower era.

Kruse masterfully excavates this tale. But it is only one episode in a larger story that runs through U.S. history, and Kruse’s book raises questions that lie beyond the scope of his study: Exactly how does religion operate in U.S. politics? What came before and after the mid-twentieth-century period that Kruse focuses on? And what’s likely to happen next in American religious politics?

GOD'S COUNTRY

Most rich nations long ago evolved from mostly religious to mostly secular. Today in France, Sweden, and the United Kingdom, fewer than 20 percent of citizens say they regularly attend church. In contrast, 40 percent of Americans say they attend services weekly, and 70 percent say they go a few times a year. The most familiar explanation for this disparity is the vibrant religious marketplace in the United States. In contrast to nations with an official church supported by taxes, the U.S. religious scene has always been open to anyone who can draw a paying congregation.

The result—locked into law by the U.S. Constitution’s protections against the establishment of an official religion—is a land of many creeds. And that, in turn, has an important political ramification: there is a religion to support every perspective. Across U.S. history, churches have inspired revolutionaries and reactionaries, abolitionists and slaveholders, liberals and conservatives. Kruse’s story focuses on the Eisenhower administration co-opting a right-wing religious revival and rendering it palatable to a broad political center. But today, religion reflects polarization rather than consensus: African American churches bus their largely Democratic congregants to the polls, while white evangelical preachers warn that it would be a sin against the Almighty to cast a “blue” vote. Many foreign observers find this astonishing; most Americans see it as perfectly normal.

Are you there, God? The Obamas at the National Prayer Breakfast, February 2012. LARRY DOWNING / REUTERS

The United States is also different from other developed countries in a less familiar way: Americans don’t mind meddling clerics. As the political scientist Anna Grzymala-Busse has recently shown, people in most rich nations condemn religious involvement in politics. Even in highly churched states, such as Croatia, Ireland, Poland, and Portugal, between 70 and 90 percent of the public rejects religious efforts to influence government. Americans have been much slower to object (although impatience has been on the rise). The difference might stem, once again, from the multiplicity of U.S. religious politics; in contrast to places where religion stoutly supports the ancien régime, in the United States, every political faction draws on religion.

In broad historical terms, religion cycles through American politics in three great steps. First, preachers denounce a rising tide of secularism, false religion, and the government policies that encourage them. Occasionally, these jeremiads leak into mainstream culture and the mass media begin to reverberate with a warning: Change your ways, Americans, or there will be hell to pay.

The second phase begins when a powerful politician—during the twentieth century, usually a president—answers the religious call and champions the crusade, ushering the religious reformers and their ideas into his or her political coalition. The reformers win some changes but grow disillusioned when the reforms fail to live up to expectations. Politicians make unreliable moralists, leaving the churches to rediscover an ancient truth: religious life, devoted to fundamental principles, sits awkwardly in the world of power and political expediency.

In the final stage, after achieving some goals and seeing others watered down or cast aside, the movement begins to come apart, as every coalition (and revival) eventually does. Fervor wanes. The religious battalions get tired of compromising and drift away from politics—until a new generation of activists springs up and the cycle begins again.

BIG TENT REVIVAL

That cycle has shaped three religious revivals during the past 80 years: think of them as the Roosevelt, Eisenhower, and Reagan dispensations. In each case, a president seized on a powerful religious movement and used it to rewrite the American relationship between politics and faith.

In the early twentieth century, what came to be known as the Social Gospel movement rose up in the mainline Protestant churches and called on Christians to focus on economic injustice. Its adherents demanded fair wages, aid for the poor, the prohibition of liquor, women’s rights, child labor laws, and steps to drastically reduce economic inequality. In the 1930s, President Franklin Roosevelt used the movement to define his policies and denounce his enemies. For example, Roosevelt introduced his plan for Social Security in what he described as a “Sunday sermon.” Catholics, Protestants, and Jews all condemn the “unbrotherly . . . distribution of wealth,” preached Roosevelt, yet the “spirit of Mammon” has crowded out the “eternal principles of God and justice.” The Roosevelt administration touted the president’s agenda as not merely sound policy but also “the Christian thing to do.”

Roosevelt, Eisenhower, and Reagan all seized on powerful religious movements and used them to rewrite the American relationship between politics and faith.

Roosevelt and the New Dealers were selective when it came to putting the Social Gospel into practice, casting aside Prohibition and mostly ignoring the women’s agenda. But they crafted a highly religious attack on wealth and privilege. “The moneychangers have fled from their high seats in the temple of our civilization,” said Roosevelt in his first inaugural address. “We may now restore that temple to the ancient truths,” to “social values more noble than mere monetary profit.” Future Democrats would invoke the Social Gospel—President Barack Obama regularly uses the term—but they would leave out the harsh bits about Mammon and the moneychangers; in these Gordon Gekko times, Roosevelt’s Christian rhetoric sounds radical.

Kruse offers an excellent guide to the next part of the story: a conservative Christian backlash against the New Deal’s version of the Social Gospel. Conservative ministers warned that collectivism offered no path to salvation, public works did not amount to worship, and a faith focused on material matters squandered all of religion’s awe and transcendence. The critique slowly gathered adherents and, as Americans began to turn rightward after World War II, swelled into a national revival.

When Eisenhower took office in 1953, he championed conservative religious ideals, seeing in them the potential to unify Americans during the Cold War. He began his first inaugural address by asking, “Would you permit me the privilege of uttering a little private prayer of my own?” For over a minute, the president beseeched God for cooperation and understanding among people “of differing political faiths.” A month earlier, he had made his most famous religious declaration: “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.” Liberal intellectuals hooted: “a very fervent believer in a very vague religion,” scorned the theologian William Lee Miller. But Congress eagerly signed on to Eisenhower’s ceremonial deism and churned out one emblem of “Christian America” after another, with almost no opposition. Even the American Civil Liberties Union declined to object as the U.S. government infused itself with symbols of Christianity.

But the symbols were the easy part. The limits of this national revival came into focus when policymakers got down to practical details. Most Americans agreed that schoolchildren ought to pray, but exactly which prayers should they say? Faith tugged local officials toward Christian prayer in Mississippi, Mormon prayer in Utah, and nondenominational prayer in New York—which evangelicals denounced as no prayer at all, since it failed to mention Jesus. Finally, in 1962, the U.S. Supreme Court stepped in and declared that all school prayers breached Jefferson’s wall and were unconstitutional. A similar effort to mandate the presence of Bibles in schools collapsed when different faiths insisted on different translations.

THE GREAT CHRISTIAN COMMUNICATOR

The chaos of the 1960s buried whatever remained of the establishmentarian religious consensus that had thrived during the 1950s. White Americans (outside the South, at least) came to cheer Martin Luther King, Jr.’s Christian nonviolence but were baffled by the rising black Muslim leaders who challenged King. Meanwhile, a new generation of Jeremiahs condemned the hedonistic American people and the immoral state that ruled them. When Congress passed the Equal Rights Amendment in 1972 (still yet to be ratified) and the Supreme Court struck down abortion restrictions in 1973, the religious right rushed back into politics. The Moral Majority became the most visible organization preaching an increasingly popular sermon: pro-life, pro-traditional family, pro-morality, and pro-American. The movement soon found a formidable champion in California’s governor, Ronald Reagan.

When Reagan accepted the Republican nomination for president in 1980, he stopped in the middle of his acceptance speech and went off script, deftly alluding to some shadowy authority that might punish him for performing a forbidden act. “I have thought of something that is not part of my speech and I’m worried over whether I should do it,” he said, before plunging on: “We begin our crusade joined together in a moment of silent prayer.” The following month, Reagan addressed a national gathering of evangelical and fundamentalist ministers. “I know you can’t endorse me,” he said, again referencing a wall that unjustly separated church and state (and prevented the tax-exempt religious groups from directly aiding his campaign). “But,” Reagan added, “I want you to know that I endorse you.”

Joel Osteen gives the invocation before Annise Parker is publicly sworn in as mayor of Houston, Texas, January 2010. RICHARD CARSON / REUTERS

The Reagan administration introduced religious reforms, changed the tone of American politics, and, inevitably, disappointed its more ardent evangelical supporters. Before Reagan’s tenure, roughly half of all presidential addresses ended with an invocation of God; after him, the number soared to around 90 percent. By drawing Christian fundamentalists into the governing coalition, Reagan committed his party to a fierce attack on abortion, a soft endorsement of biblical inerrancy, and a tough, moralizing stance on bad behavior of every sort. Two existing policies—the “wars” on drugs and crime—became centerpieces of his policy agenda. Crime and poverty, said the president again and again, were not the results of racism or hard times, as the old Social Gospel suggested. Echoing Fifield’s message, Reagan insisted that individuals be held accountable for their own actions. Owing in great part to policies put in place during the Reagan years, the number of Americans behind bars rose fivefold during the 1980s and 1990s.

Reagan’s framing of public policy in moral terms continued to shape politics long after he’d left office. Christian conservatives had no fondness for President Bill Clinton, but on some issues, Clinton hewed fairly closely to the moralism of the Reagan era—for example, ending traditional welfare, which critics had denounced for promoting laziness and promiscuity, and embracing a law-and-order agenda that funded the hiring of around 100,000 new police officers across the nation. The George W. Bush administration even more explicitly embraced moral and religious themes, especially in the aftermath of the 9/11 attacks, when Bush spoke unabashedly about crusades and evildoers.

In the coming years, a full-throated new "social gospel" might rise out of the country’s black churches.

Yet despite its political influence on three decades of U.S. politics, the religious right never quite savored victory. Its most cherished goals—ending abortion, restoring traditional families, cleaning up the culture—remained out of reach. And during the Obama years, the moral and religious climate has shifted even more firmly away from conservative Christian ideals: consider, for instance, the spread of same-sex marriage and the decriminalization and even legalization, in some places, of marijuana. Young people have turned decisively away from organized religion; according to a recent study conducted by the Pew Research Center, more than a third of Americans under age 33 do not identify with any church—an unprecedented figure. The trend is particularly stark within Christianity: only 71 percent of Americans now describe themselves as Christian, reflecting a drop of nearly eight percentage points in the past seven years alone. For those reasons, Christian conservatism, although hardly a spent force, will likely wane as a political movement, as the religious politics of the United States seem to have reached another inflection point.

FAITH NO MORE?

Religious ideas emerge and gain momentum over years before finding a political champion. What might the next phase of Christian politics in the United States look like? Two very different possibilities stand out.

First, a full-throated new social gospel might rise out of the country’s black churches. Most Americans got their first taste of this possible future in 2008, when they heard snippets of a sermon by Obama’s former pastor, Jeremiah Wright, including the infamous line “Not ‘God Bless America’: God damn America!” But the media storm that engulfed Wright blew right past the preacher’s old-fashioned message: God has grown wrathful over his chosen people’s iniquity and will continue to punish them unless they change their ways. The country’s transgression, as Wright described it, was the traditional Social Gospel sin: “treating our citizens as less than human.” The solutions, Wright insisted, lay in the familiar agenda of racial and social justice.

Although both the left and the right repudiated Wright himself, the next dispensation may very well flow out of majority-black churches like Wright’s. African Americans represent the single most churched group in the nation. Historically black denominations present a fully developed religious vision that draws on both the Social Gospel and the legacy of the civil rights crusade. Outrage over police killings of unarmed black men has produced huge protests all over the country during the past year and could very well spark a powerful moral movement.

So-called prosperity preachers and libertarians might find common ground around the idea that individuals should save themselves, without drug wars or welfare programs.

Black religious fervor would be especially formidable if it forged an alliance between African Americans and Hispanic Americans, another group with high rates of church attendance. Both groups bear the brunt of militarized policing and harsh sentencing; both have rallied for social justice, a living wage, and better government services. Together, they compose around 30 percent of the U.S. population. Although there are undeniable tensions between the communities, less likely partners have forged religious coalitions in recent times. The challenge will be finding effective leaders to foster such an alliance and bring it to political power.

Another very different possibility lies in the “prosperity gospel.” Many contemporary American pastors have cast aside their hellfire sermons and started focusing instead on personal fulfillment—and riches. God will show you how to “move forward into your bright future,” declares the megachurch minister Joel Osteen. The hip-hop artist Mary J. Blige offers a more ecstatic version of the message. “My God is a God who wants me to have things,” she told an interviewer in 2006. “He wants me to bling!”

The prosperity gospel mixes the Christian ideal of individual salvation with the bootstrapping ethos of Horatio Alger, then adds a touch of New Age blather. It would neatly complement the rising libertarian movement in the United States. Prosperity preachers and libertarians might find common ground around the idea that individuals should save themselves, without drug wars or welfare programs. Prosperity-gospel Christians could provide a moral grounding for the nascent political coalitions around libertarians such as U.S. Senator Rand Paul—pulling together young people cheering legal marijuana and economic conservatives calling for cuts to entitlements.

Kruse’s thoughtful book illustrates a kind of life cycle of American religious politics: fervent social movements rise up, crest with presidential support, and then slip away, leaving behind rituals, rhetoric, rules, and reforms. It is, of course, impossible to know the next turn of the cycle. But if history is a reliable guide, the next moral moment is already stirring somewhere in the culture and waiting for a coalition to push it toward political power.