I am someone who believes that religious liberty is the country’s founding freedom, the idea that made America possible. I am also a homosexual atheist, so religious conservatives may not want my advice. I’ll give it to them anyway. Culturally conservative Christians are taking a pronounced turn toward social secession: asserting both the right and the intent to sequester themselves from secular culture and norms, including the norm of nondiscrimination. This is not a good idea. When religion isolates itself from secular society, both sides lose, but religion loses more.

Over the decades, religious traditionalists’ engagement with American secular life has waxed and waned. After the public-relations disaster of the Scopes evolution trial in the 1920s, many conservative Christians recoiled from politics, only to come out swinging in the 1970s, when the Moral Majority and other elements of what came to be called the religious right burst onto the scene. If you believe in cultural cycles, perhaps we’re due for another withdrawal. Certainly, the breakthrough of gay marriage has fed disillusionment and bewilderment. “I suspect the initial reaction among evangelicals is going to be retreat and hope to be left alone,” Maggie Gallagher, a prominent gay-marriage opponent, recently told The Huffington Post.

Still, the desire to be left alone takes on a pretty aggressive cast when it involves slamming the door of a commercial enterprise on people you don’t approve of. The idea that serving as a vendor for, say, a gay commitment ceremony is tantamount to “endorsing” homosexuality, as the new religious-liberty advocates now assert, is a far-reaching proposition, one with few apparent outer boundaries in a densely interwoven mercantile society. It suggests a hair-trigger defensiveness about religious identity that would have seemed odd just a few years ago. As far as I know, during the divorce revolution it never occurred to, say, Catholic bakers to tell remarrying customers, “Your so-called second marriage is a lie, so take your business elsewhere.” That would have seemed not so much principled as bizarre.

Why the hunkering down? When I asked around recently, a few answers came back. One is the fear that traditional religious views, especially about marriage, will soon be condemned as no better than racism, and that religious dissenters will be driven from respectable society, denied government contracts, and passed over for jobs—a fear heightened by well-publicized stories like the recent one about the resignation of Mozilla’s CEO, who had donated to the campaign against gay marriage in California. After a talk I gave recently in Philadelphia on free speech, a woman approached me claiming that the school system where she works harasses and fires anyone who questions gay marriage. I wanted to point out that in most states it’s perfectly legal to fire people just for being gay, whereas Christians enjoy robust federal and state antidiscrimination protections, but the look in her eyes was too fearful for convincing. Perhaps it is natural for worried people to daydream about some kind of escape. One Christian acquaintance told me, “I say half jokingly to my wife, ‘Where do we move?’ ”

A second factor is the failed promise of what seemed, around the turn of the millennium, to be a grand new partnership between our elected and religious leaders. John DiIulio, a University of Pennsylvania political scientist, remembers that time vividly: He was the founding director of the White House Office of Faith-Based and Community Initiatives, under President George W. Bush. In 1999, he recalls, Vice President Al Gore and then–Texas Governor Bush had thrown their support behind a dramatic expansion of government’s collaboration with faith-based groups, in an effort to ameliorate social problems like poverty, hunger, and family breakdown; a new secular-religious entente seemed aborning. But trust eroded, DiIulio says, and then collapsed as factions on both sides, especially the right, drew red lines, set conditions, and lawyered up. Now it’s the “war on religion” versus the “war on women,” and court dockets are full of religious-liberty cases. (Hobby Lobby is just one in a series.) “The lines have hardened so much,” DiIulio says.