Nowadays not even theologians are interested in theology. They tell me it's because Kant proved that theology was impossible and the logical positivists nailed it by showing that theological claims were not merely unknowable but unintelligible. Most theologians are therefore "non-realists" when it comes to religious claims – that is, they don't believe in God.
By the late 20th century "mainline" churches in the US, even if they did not profess non-realism, operated as if theology were unimportant and uninteresting. Convinced that their primary purpose was social improvement, church leaders regarded theological differences as inconsequential and denominational divisions as an impediment to their collaborative work for social justice. And so liberal ecumenism was born, the first moment in what we can now see was a great realignment.
The second soon followed. Conservative evangelical groups, once bitterly divided over theological minutiae, coalesced to form the religious right.
Like liberal ecumenists, conservatives united to promote a social agenda: evangelicals joined forces to campaign against modernity. Conservatives insisted that their own programme was backed by real theology. But they happily collaborated –and collaborate still – with anyone, including conservative Catholics, who was on board with their social vision. Any theology would do so long as it supported "family values": sex roles, sexual abstinence outside of heterosexual marriage, and discipline to maintain a social order threatened by the collapse of traditional social arrangements. Theology was negotiable; lifestyle was not.
Politics were also negotiable. Once evangelicalism had become the normative form of non-Catholic Christianity in America, a new generation of evangelical mega-church pastors cultivated a softer image and went mainstream on a range of political policies. But on core social issues there was no compromise. Evangelicals might take up environmentalism or criticise American military adventurism, but they would not repudiate "family values."
The Roman Catholic church too, though politically centre-left, was uncompromising when it came to sex roles and sexuality. Anglican and Roman Catholic ecumenists painstakingly negotiated fine points of theology while everyone knew that women's ordination was a deal-breaker. Sex roles were central to the Catholic church's conservative communitarian vision: the doctrine that gender was ontologically grounded was non-negotiable.
For now, the conservative social agenda still sells. Conservative churches flourish in the global south where their social vision, of a world where women's lives centre on the family under male headship and paternalistic clergy provide moral guidance and leadership, is still acceptable.
Where social change has disrupted lives, conservative churches provide a refuge from modernity. During the late 20th century, without strong labour unions or social safety nets, the American working class suffered disproportionately from the shift to a service sector economy. Nostalgic for an idealised past, when manufacturing jobs provided a "family wage," marriages were stable and neighborhoods safe, they cling, in Obama's words, to guns and religion.
Conservatives note with satisfaction that Christianity is thriving in developing countries, amongst immigrants, and within the American working class. Modernity, they believe, is a failed experiment. Fertile, socially conservative immigrants will replace declining secular European populations and the balance of power will shift to the global south, where "family values" persist.
But fertility rates have fallen precipitously in many developing countries. Female literacy and the economic emergence of women lower fertility rates, promote economic development and track the passage from an agrarian society to a modern one. Conservatives who look to the developing world as the church's hope for the future can only pray for an increase in poverty and female illiteracy to stem the tide of modernity.
In the US, conservative churches are still growing though not as rapidly as America's fastest growing "religious group": the unchurched. In light of statistical analyses, some evangelicals are already predicting the collapse of evangelical Christianity as evangelical churches approach a "generational horizon".
Christianity insofar as it is identified with a social agenda, whether liberal or conservative, will lose. Liberal churches are dying. Non-realist theology has little popular appeal: most laypeople who don't believe in God see no reason to go to church. There are innumerable secular organisations devoted to promoting social improvement and no reason why they should work for social justice under religious auspices. Conservative churches are identified with a social agenda that an increasing number of people find unacceptable.
Maybe it's time for churches to re-engage with theology, arguments concerning the existence and nature of God, and even with mysticism, the quest for direct experience of God. Almost one fifth of Americans call themselves "spiritual, but not religious." Organised religion has failed them. They reject conservative churches' social agendas and liberal churches, having gutted their liturgies to strip out every last bit of the numinous, have little to offer them.
Arguably, theology and mysticism are all Christianity has to offer. The illusion that churches "witness" to the world and have an essential social role to play is unsustainable. The best churches can do is provide religious goods and services for the minority of consumers, among whom I include myself, who have a taste for religion.