This hard secularism is a relatively radical idea in the American context, where the separation of church and state has rarely separated God from politics: From abolitionist and “Social Gospel” activism in the 19th century to the civil-rights and anti-abortion movements of the 20th, religiously motivated political action has been a regular feature of our national life. Indeed, the America that many secularists seem to desire looks an awful lot like the Europe of today, where politicians who mention God are a rarity, and governments keep a wary eye on “sects” that stray too far outside the mainstream.
Yet the Europe of tomorrow may look more like … the United States, with a politics that’s increasingly shaped by clashes between believers, or between belief and unbelief. Already, the Continent is experiencing a low-grade culture war, created by the collision between the religious zeal of Muslim immigrants and the secular culture that surrounds them. In flash points that range from the murder of the anti-Islamic filmmaker Theo Van Gogh in Holland, to the controversy over the supposedly blasphemous Danish cartoons, to the question of whether to admit Turkey to the EU, secular Europe has found itself in unfamiliar, God-haunted, almost American territory. Such disputes may subside as Islamic immigrants assimilate to European norms, but for now, at least, resistance to assimilation by Muslims suggests that they may succeed in changing those norms as much as they are changed by them.
Meanwhile, there are signs that Christianity, too, is emerging from its decades-long defensive crouch. Pope Benedict XVI has taken the re-Christianization of Europe as a theme of his papacy, and his church’s recent interventions in Spain’s debate over same-sex unions and in Italy’s referendum on whether to loosen restrictions on in vitro fertilization bear an unmistakable resemblance to the gauntlet-throwing that Americans have come to expect from their churchmen.
In each case, demography may be pushing religion back into European politics. The Muslim birthrate in Europe is far higher than the birthrate among non-Muslims, and immigration from the Islamic world continues apace. Meanwhile, immigrants from Africa and Latin America have injected a new vitality into European Christianity, creating thriving Evangelical and Pentecostal communities in urban areas where many of the established churches stand empty. It was Christians’ demographic advantage in the ancient world, the sociologist Rodney Stark has suggested, that helped their faith take over Europe in the first place, and high fertility rates help explain the growth of evangelical Christianity and Mormonism in the United States over the last century. Now similar demographic forces, the political scientist Eric Kaufmann argued last year in the British magazine Prospect, may be “carrying Europe towards a more American model of modernity,” in which the wall of separation between church and state looks more like a picket fence, easily scaled or shimmied through.
These trends shouldn’t be exaggerated. America remains a deeply religious nation and its secularists an embattled minority, while Europeans remain strongly invested in preventing faith from intruding into politics. But both continents may be drifting into a zone where religious belief is likely to be a persistent source of tension, rather than a commonplace or a curiosity.
Religion stirs up the most controversy, a group of Harvard economists recently argued, when roughly half the population is actively religious; conflict ebbs when the devout constitute large majorities or small minorities. The more evenly divided a culture finds itself on the ultimate questions, the more likely politicians are to pursue “strategic extremism” and mobilize one side against the other. Precisely this kind of polarization dominated European politics from the French Revolution until the middle of the 20th century, sparking regular clashes— Germany’s Kulturkampf, France’s Dreyfuss Affair, Spain’s Civil War—between secular and religious ideologies.
America has long avoided this trap by enjoying near-universal piety; Europe, at least lately, has escaped it by cultivating near-universal skepticism. But if the religious gulf between the two continents narrows, the divides within each one are likely to open ever wider, and religious peace turn increasingly to culture war—or worse.