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The idea of American exceptionalism has become so dubious that much of its modern usage is merely sarcastic. But when it comes to religion, Americans really are exceptional. No rich country prays nearly as much as the U.S, and no country that prays as much as the U.S. is nearly as rich.

America’s unique synthesis of wealth and worship has puzzled international observers and foiled their grandest theories of a global secular takeover. In the late 19th century, an array of celebrity philosophers—the likes of Friedrich Nietzsche, Karl Marx, and Sigmund Freud—proclaimed the death of God, and predicted that atheism would follow scientific discovery and modernity in the West, sure as smoke follows fire.

Stubbornly pious Americans threw a wrench in the secularization thesis. Deep into the 20th century, more than nine in 10 Americans said they believed in God and belonged to an organized religion, with the great majority of them calling themselves Christian. That number held steady—through the sexual-revolution ’60s, through the rootless and anxious ’70s, and through the “greed is good” ’80s.

But in the early 1990s, the historical tether between American identity and faith snapped. Religious non-affiliation in the U.S. started to rise—and rise, and rise. By the early 2000s, the share of Americans who said they didn’t associate with any established religion (also known as “nones”) had doubled. By the 2010s, this grab bag of atheists, agnostics, and spiritual dabblers had tripled in size.

History does not often give the satisfaction of a sudden and lasting turning point. History tends to unfold in messy cycles—actions and reactions, revolutions and counterrevolutions—and even semipermanent changes are subtle and glacial. But the rise of religious non-affiliation in America looks like one of those rare historical moments that is neither slow, nor subtle, nor cyclical. You might call it exceptional.

The obvious question for anybody who spends at least two seconds looking at the graph above is: What the hell happened around 1990?

According to Christian Smith, a sociology and religion professor at the University of Notre Dame, America’s nonreligious lurch has mostly been the result of three historical events: the association of the Republican Party with the Christian right, the end of the Cold War, and 9/11.

This story begins with the rise of the religious right in the 1970s. Alarmed by the spread of secular culture—including but not limited to the sexual revolution, the Roe v. Wade decision, the nationalization of no-fault divorce laws, and Bob Jones University losing its tax-exempt status over its ban on interracial dating—Christians became more politically active. The GOP welcomed them with open arms. The party, which was becoming more dependent on its exurban-white base, needed a grassroots strategy and a policy platform. Within the next decade, the religious right—including Ralph Reed’s Christian Coalition, James Dobson’s Focus on the Family, and Jerry Falwell’s Moral Majority—had become fundraising and organizing juggernauts for the Republican Party. In 1980, the GOP social platform was a facsimile of conservative Christian views on sexuality, abortion, and school prayer.

The marriage between the religious and political right delivered Reagan, Bush, and countless state and local victories. But it disgusted liberal Democrats, especially those with weak connections to the Church. It also shocked the conscience of moderates, who preferred a wide berth between their faith and their politics. Smith said it’s possible that young liberals and loosely affiliated Christians first registered their aversion to the Christian right in the early 1990s, after a decade of observing its powerful role in conservative politics.

Second, it may have felt unpatriotic to confess one’s ambivalence toward God while the U.S. was locked in a geopolitical showdown with a godless Evil Empire. In 1991, however, the Cold War ended. As the U.S.S.R. dissolved, so did atheism’s association with America’s nemesis. After that, “nones” could be forthright about their religious indifference, without worrying that it made them sound like Soviet apologists.

Third, America’s next geopolitical foe wasn’t a godless state. It was a God-fearing, stateless movement: radical Islamic terrorism. A series of bombings and attempted bombings in the 1990s by fundamentalist organizations such as al-Qaeda culminated in the 9/11 attacks. It would be a terrible oversimplification to suggest that the fall of the Twin Towers encouraged millions to leave their church, Smith said. But over time, al-Qaeda became a useful referent for atheists who wanted to argue that all religions were inherently destructive.

Meanwhile, during George W. Bush’s presidency, Christianity’s association with unpopular Republican policies drove more young liberals and moderates away from both the party and the Church. New Atheists, such as Christopher Hitchens and Sam Harris, became intellectual celebrities; the 2006 best seller American Theocracy argued that evangelicals in the Republican coalition were staging a quiet coup that would plunge the country into disarray and financial ruin. Throughout the Bush presidency, liberal voters—especially white liberal voters— detached from organized religion in ever-higher numbers.

Religion has lost its halo effect in the past three decades, not because science drove God from the public square, but rather because politics did. In the 21st century, “not religious” has become a specific American identity—one that distinguishes secular, liberal whites from the conservative, evangelical right.

Other social forces, which have little to do with geopolitics or partisanship, have played a key role in the rise of the nones.

The Church is just one of many social institutions—including banks, Congress, and the police—that have lost public trust in an age of elite failure. But scandals in the Catholic Church have accelerated its particularly rapid loss of moral stature. According to Pew research, 13 percent of Americans today self-identify as “former Catholics,” and many of them leave organized religion altogether. And as the ranks of the nones have swelled, it’s become more socially acceptable for casual or rare churchgoers to tell pollsters that they don’t particularly identify with any faith. It’s also become easier for nones to meet, marry, and raise children who grow up without any real religious attachment.

Nor does Smith rule out the familiar antagonists of capitalism and the internet in explaining the popularity of non-affiliation. “The former has made life more precarious, and the latter has made it easier for anxious individuals to build their own spiritualities from ideas and practices they find online,” he said, such as Buddhist meditation guides and atheist Reddit boards.

Most important has been the dramatic changes in the American family. The past half century has dealt a series of body blows to American marriage. Divorce rates spiked in the ’70s through the ’90s, following the state-by-state spread of no-fault divorce laws. Just as divorce rates stabilized, the marriage rate started to plummet in the ’80s, due to both the decline of marriage within the working class and delayed marriage among college-educated couples.

“There’s historically been this package: Get married, go to church or temple, have kids, send them to Sunday school,” Smith said. But just as stable families make stable congregations, family instability can destabilize the Church. Divorced individuals, single parents, and children of divorce or single-parent households are all more likely to detach over time from their congregations.

Finally, the phenomenon of “delayed adulthood” might be another subtle contributor. More Americans, especially college graduates in big metro areas, are putting off marriage and childbearing until their 30s, and are using their 20s to establish a career, date around, and enjoy being young and single in a city. By the time they settle down, they have established a routine—work, brunch, gym, date, drink, football—that leaves little room for weekly Mass. “They know who they are by 30, and they don’t feel like they need a church to tell them,” Smith said.

The rise of the nones shows no signs of slowing down. In fact, the religious identity that seems to be doing the best job at both retaining old members and attracting new ones is the newfangled American religion of Nothing Much at All.

Does the rise of the nones matter?

Let’s first consider the possibility that it doesn’t. As America’s youth have slipped away from organized religion, they haven’t quite fallen into wickedness. If anything, today’s young people are uniquely conscientious—less likely to fight, drink, use hard drugs, or have premarital sex than previous generations. They might not be able to quote from the Book of Matthew, but their economic and social politics—which insist on protections for the politically meek and the historically persecuted—aren’t so far from a certain reading of the beatitudes.

But the liberal politics of young people brings us to the first big reason to care about rising non-affiliation. A gap has opened up between America’s two political parties. In a twist of fate, the Christian right entered politics to save religion, only to make the Christian-Republican nexus unacceptable to millions of young people—thus accelerating the country’s turn against religion.

Although it would be wrong to call Democrats a secular party (older black voters are highly religious and dependably vote Democratic), the left today has a higher share of religiously unaffiliated voters than anytime in modern history. At the same time, the average religiosity of white Christian Republicans has gone up, according to Robert P. Jones, the CEO of the polling firm PRRI and the author of The End of White Christian America. Evangelicals feel so embattled that they’ve turned to a deeply immoral and authoritarian champion to protect them—even if it means rendering unto an American Caesar whatever the hell he wants. American politics is at risk of becoming a war of religiosity versus secularism by proxy, where both sides see the other as a catastrophic political force that must be destroyed at all costs.

The deeper question is whether the sudden loss of religion has social consequences for Americans who opt out. Secular Americans, who are familiar with the ways that traditional faiths have betrayed modern liberalism, may not have examined how organized religion has historically offered solutions to their modern existential anxieties.

Making friends as an adult without a weekly congregation is hard. Establishing a weekend routine to soothe Sunday-afternoon nerves is hard. Reconciling the overwhelming sense of life’s importance with the universe’s ostensible indifference to human suffering is hard.

Although belief in God is no panacea for these problems, religion is more than a theism. It is a bundle: a theory of the world, a community, a social identity, a means of finding peace and purpose, and a weekly routine. Those, like me, who have largely rejected this package deal, often find themselves shopping à la carte for meaning, community, and routine to fill a faith-shaped void. Their politics is a religion. Their work is a religion. Their spin class is a church. And not looking at their phone for several consecutive hours is a Sabbath.

American nones may well build successful secular systems of belief, purpose, and community. But imagine what a devout believer might think: Millions of Americans have abandoned religion, only to re-create it everywhere they look.

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