There it was, an old term with new urgency: post-Christian. This is not to say that the Christian God is dead, but that he is less of a force in American politics and culture than at any other time in recent memory. To the surprise of liberals who fear the advent of an evangelical theocracy and to the dismay of religious conservatives who long to see their faith more fully expressed in public life, Christians are now making up a declining percentage of the American population.

According to the American Religious Identification Survey that got Mohler’s attention, the percentage of self-identified Christians has fallen 10 percentage points since 1990, from 86 to 76 percent. The Jewish population is 1.2 percent; the Muslim, 0.6 percent. A separate Pew Forum poll echoed the ARIS finding, reporting that the percentage of people who say they are unaffiliated with any particular faith has doubled in recent years, to 16 percent; in terms of voting, this group grew from 5 percent in 1988 to 12 percent in 2008—roughly the same percentage of the electorate as African-Americans. (Seventy-five percent of unaffiliated voters chose Barack Obama, a Christian.) Meanwhile, the number of people willing to describe themselves as atheist or agnostic has increased about fourfold from 1990 to 2009, from 1 million to about 3.6 million. (That is about double the number of, say, Episcopalians in the United States.)

While we remain a nation decisively shaped by religious faith, our politics and our culture are, in the main, less influenced by movements and arguments of an explicitly Christian character than they were even five years ago. [...] As crucial as religion has been and is to the life of the nation, America’s unifying force has never been a specific faith, but a commitment to freedom—not least freedom of conscience. At our best, we single religion out for neither particular help nor particular harm; we have historically treated faith-based arguments as one element among many in the republican sphere of debate and decision. The decline and fall of the modern religious right’s notion of a Christian America creates a calmer political environment and, for many believers, may help open the way for a more theologically serious religious life.

On a vaguely related topic, there is the debate in the world on the freedom to defame religion.