When I was an atheist back in the 1960s, its future seemed assured. I grew up in Northern Ireland, where religious tensions and violence had alienated many from Christianity. Like so many disaffected young people then, I rejected religion as oppressive, hypocritical, a barbarous relic of the past. The sociologists were predicting that religion would soon die out; if not, suitably enlightened governments and social agencies could ensure that it was relegated to the margins of culture, the last refuge of the intellectually feeble and socially devious. The sooner it was eliminated, the better place the world would be.

Atheism then had the power to command my mind and excite my heart. It made sense of things, and offered a powerful vision of the future. The world would be a better place once religion ended. It was simply a matter of time, judiciously aided by direct action here and there. Although I am no longer an atheist, I retain a profound respect for its aspirations for humanity and legitimate criticisms of dysfunctional religion. Yet the sun seems to be setting on this shopworn, jaded and tired belief system, which now lacks the vitality that once gave it passion and power.

To suggest that atheism is a belief system or faith will irritate some of its followers. For them, atheism is not a belief; it is the Truth. There is no god, and those who believe otherwise are deluded, foolish or liars (to borrow from the breezy rhetoric of Britain’s favourite atheist, the scientific populariser turned atheist propagandist Richard Dawkins). But it’s now clear that the atheist case against God has stalled. Surefire philosophical arguments against God have turned out to be circular and self-referential.

The most vigorous intellectual critique of religion now comes from Dawkins, who has established himself as atheism’s leading representative in the public arena. Yet a close reading of his works — which I try to provide in my forthcoming book Dawkins’ God: Genes, Memes and the Meaning of Life — suggests that his arguments rest more on fuzzy logic and aggressive rhetoric than on serious evidence-based argument. As America’s leading evolutionary biologist, the late Stephen Jay Gould, insisted, the natural sciences simply cannot adjudicate on the God question. If the sciences are used to defend either atheism or religious beliefs, they are misused.

Yet atheism has not simply run out of intellectual steam. Its moral credentials are now severely tarnished. Once, it was possible to argue that religion alone was the source of the world’s evils. Look at the record of violence of the Spanish Inquisition (interestingly, recent research has challenged this historical stereotype). Or the oppression of the French people in the 1780s under the Roman Catholic Church and the Bourbon monarchy. The list could be extended endlessly to make the same powerful moral point: wherever religion exercises power, it oppresses and corrupts, using violence to enforce its own beliefs and agendas. Atheism argued that it abolished this tyranny by getting rid of what ultimately caused it — faith in God.

Yet that argument now seems tired, stale and unconvincing. It was credible in the 19th century precisely because atheism had never enjoyed the power and influence once exercised by religion. But all that has changed. Atheism’s innocence has now evaporated. In the 20th century, atheism managed to grasp the power that had hitherto eluded it. And it proved just as fallible, just as corrupt and just as oppressive as anything that had gone before it. Stalin’s death squads were just as murderous as their religious antecedents. Those who dreamed of freedom in the new atheist paradise often found themselves counting trees in Siberia, or confined to the gulags — and they were the fortunate ones.

Like many back in the late 1960s, I was quite unaware of the darker side of atheism, as practised in the Soviet Union. I had assumed that religion would die away naturally, in the face of the compelling intellectual arguments and moral vision offered by atheism. I failed to ask what might happen if people did not want to have their faith eliminated. A desire to eliminate belief in God at the intellectual or cultural level has the most unfortunate tendency to encourage others to do this at the physical level. Lenin, frustrated by the Russian people’s obstinate refusal to espouse atheism voluntarily and naturally after the Russian Revolution, enforced it, arguing in a famous letter of March 1922 that the ‘protracted use of brutality’ was the necessary means of achieving this goal.

Some of the greatest atrocities of the 20th century were committed by regimes which espoused atheism, often with a fanaticism that some naive Western atheists seem to think is reserved only for religious people. As Martin Amis stressed in Koba the Dread, we now know what really happened under Stalin, even if it was unfashionable to talk about this in progressive circles in the West until the 1990s. The firing squads that Stalin sent to liquidate the Buddhist monks of Mongolia gained at least something of their fanaticism and hatred of religion from those who told them that religion generated fanaticism and hatred.

The real truth here seems to be that identified by Nietzsche at the end of the 19th century — that there is something about human nature which makes it capable of being inspired by what it believes to be right to do both wonderful and appalling things. Neither atheism nor religion may be at fault — it might be some deeply troubling flaw in human nature itself. It is an uncomfortable thought, but one that demands careful reflection.

A further problem for atheism is that its appeal seems to be determined by its social context, not intrinsic to its ideas. Where religion is seen to oppress, confine, deprive and limit, atheism may well be seen to offer humanity a larger vision of freedom. But where religion anchors itself in the hearts and minds of ordinary people, is sensitive to their needs and concerns, and offers them a better future, the atheist critique is unpersuasive. In the past, atheism offered a vision which captured the imagination of Western Europe. We all need to dream, to imagine a better existence — and atheism empowered people to overthrow the past, and create a brave new world.

The appeal of atheism as a public philosophy came to an undistinguished end in 1989 with the collapse of the Berlin Wall. Atheism, once seen as a liberator, was now cordially loathed as an oppressor. The beliefs were pretty much the same as before; their appeal, however, was very different. As the Soviet empire crumbled at a dizzying rate in the 1990s, those who had once been ‘liberated’ from God rushed to embrace him once more. Islam is resurgent in central Soviet Asia, and Orthodoxy in Russia itself. Harsh and bitter memories of state-enforced atheism linger throughout Eastern Europe, with major implications for the religious and cultural future of the European Union as former Soviet bloc nations achieve membership.

Where people enjoy their religion, seeing it as something life-enhancing and identity-giving, they are going to find atheism unattractive. The recent surge of evidence-based studies demonstrating the positive impact of religion on human wellbeing has yet to be assimilated by atheist writers. It is only where religion is seen as the enemy that atheism’s demands for its elimination will be taken seriously. Atheism’s problem is that its own baleful legacy in the former Soviet Union has led many to view it as the enemy, and religion as its antidote. In Eastern Europe, atheism is widely seen as politically discredited and imaginatively exhausted.

But what of Western Europe, which has known state Churches and a religious establishment, but never the state atheism that casts such a dark shadow over its future in the East? Surely atheism can hope for greater things here? The West, having been spared first-hand experience of atheism as the authoritarian (anti)religion of the establishment, still has some vague, lingering memories of a religious past that atheism could build on. Yet there are real problems here. For a new challenge to atheism has arisen within the West, which atheist writers have been slow to recognise and reluctant to engage — postmodernism.

Historians of ideas often note that atheism is the ideal religion of modernity — the cultural period ushered in by the Enlightenment. But that had been displaced by postmodernity, which rejects precisely those aspects of modernity that made atheism the obvious choice as the preferred modern religion. Postmodernity has thus spawned post-atheism. Yet atheism seems to be turning a blind eye to this massive cultural shift, and the implications for the future of its faith.

In marked contrast, gallons of ink have been spilled and immense intellectual energy expended by Christian writers in identifying and meeting the challenges of postmodernism. Two are of particular relevance here. First, in general terms, postmodernism is intensely suspicious of totalising worldviews, which claim to offer a global view of reality. Christian apologists have realised that there is a real challenge here. If Christianity claims to be right where others are wrong, it has to make this credible to a culture which is strongly resistant to any such claims to be telling the whole truth. Second, again in general terms, postmodernity regards purely materialist approaches to reality as inadequate, and has a genuine interest in recovering ‘the spiritual dimension to life’. For Christian apologists, this is a problem, as this new interest in spirituality has no necessary connection with organised religion of any kind, let alone Christianity. How can the Churches connect with such aspirations?

Atheism has been slow, even reluctant, to engage with either of these developments, tending to dismiss them as irrational and superstitious (Richard Dawkins is a case in point). Yet it is easy to see why the rise of postmodernity poses a significantly greater threat to atheism than to Christianity. Atheism offers precisely the kind of ‘metanarrative’ that postmodern thinkers hold to lead to intolerance and oppression. Its uncompromising and definitive denial of God is now seen as arrogant and repressive, rather than as principled and moral.

The postmodern interest in spirituality is much more troubling for atheism than for Christianity. For the Christian, the problem is how to relate or convert an interest in spirituality to the Church or to Jesus Christ. But at least it points in the right direction. For the atheist, it represents a quasi-superstitious reintroduction of spiritual ideas, leading postmodernity backwards into religious beliefs that atheism thought it had exorcised. Atheism seems curiously disconnected from this shift in cultural mood. It seems that atheists are greying, inhabiting a dying modern world, while around them a new interest in the forbidden fruit of the spiritual realm is gaining the upper hand, above all among young people. Consider the immense popularity of the Alpha course, whose advertisements may be seen on London buses, and whose adherents are now said to number some 60 million worldwide; or the expansion of Pentecostalism, now attracting half a billion global followers. Even 9/11, a religiously motivated assault, did not prompt an atheist backlash, but an upsurge in interest in Islam. What, I wonder, are the implications of such developments for the future of atheism in the West?

I see no reason why atheism cannot regain some of its lost ground — but not as a public philosophy, commanding wide assent and demanding privileged access to the corridors of power. It will do so as a private belief system, respectful of the beliefs of others. Instead of exulting in disrespect and contempt for religious belief, atheism will see itself as one option among many, entitled to the same respect that it accords others. The most significant, dynamic and interesting critic of Western Christianity is no longer atheism, but a religious alternative, offering a rival vision of God — Islam. This is not what the atheist visionaries of the past wanted, but it seems to be the way things are going.