Religion has barged its way noisily and violently onto the European political stage in recent months.
Islamic radicals set bombs on commuter trains in Madrid that killed 191 people last March. Another extremist Muslim in Amsterdam is charged with brutally killing Dutch filmmaker Theo van Gogh in November. An angry mob of British Sikhs, throwing bricks and wrestling with police, stormed a theater in Birmingham last December, forcing the closure of a play they found offensive.
But in the shadow of such shocking events are signs of a quieter and less divisive return of religion and spirituality to European lives. "God is back among intellectuals," says Aleksander Smolar, a leading European thinker who heads the Stefan Batory Foundation in Warsaw and teaches at the Sorbonne in Paris. "You can feel there is a problem of soul in Europe; people are con- scious of a void and there is a certain crisis of secularism."
Seeking to fill that void, several dozen faithful Catholics gathered one recent Tuesday evening, as they do each week, to pray in the freshly painted basement of the St. Denys church in northern Paris.
One after another, standing in a circle, they gave thanks aloud to God: one woman was grateful that an argument with her son had not gotten out of hand; another prayed for continued strength to keep looking for a job; a third, in tears, thanked the Lord "for helping me put up with all the humiliation I suffer."
And then they all sang a simple hymn. Some swayed; some held their palms outstretched; others closed their eyes.
For the past nine years, the parish of St. Denys has been run by a priest from the "New Path Community," a charismatic Catholic movement that has borrowed much from the American Pentecostal tradition.
While the pews in traditional Catholic churches have emptied, the New Path and similar communities have blossomed, attracting thousands of believers to prayer groups and Sunday masses across Europe.
They are drawn, says parish priest Louis-Marc Thomy, "by the charisma of a community life. They say they feel unity and peace with us. And they find joy in rediscovering faith in a joyous manner."
On the face of it, religion has continued to suffer setbacks in Europe recently. Just last year, the French government reinforced its secular approach by banning Muslim head scarves and other religious symbols from schools.
Catholic teaching on such questions as abortion, contraception, divorce, and homosexuality, meanwhile, is honored more in the breach than in the observance.
That would seem to continue a secularist trend visible in Europe for several decades. That trend is offset, however, by a growing awareness that European secularism is an aberration in a world where religion is largely on the rise.
The prominent role that religion continues to play in American public life, meanwhile, has undermined the widespread European view that modern societies inevitably grow more secular, and that religion is an attribute of underdevelopment.
"A preoccupation with spirituality is much more present now at a religious and philosophical level" than it was a few years ago, says Dominique Moisi, a French political analyst.
In Britain, the country's largest bookseller has noticed that preoccupation, and moved to meet it. Expanding the shelf space it devotes to religious and spiritual books, "we have increased our range over the last few years," says Lucy Avery, a spokeswoman for the Waterstone's chain.
Sales of such books rose by nearly 4 percent last year, she adds, and titles such as the Dalai Lama's "The Art of Happiness" and a modern-language "Street Bible" have become bestsellers.
"I have noticed that a lot of general-interest publishers are turning to religious books now for commercial reasons, because that is what the public wants," says Laurence Vandamme, a spokeswoman for Cerf, the largest French religious publisher.
In France, leading philosopher Régis Debray, once a comrade in arms of Che Guevara in the Bolivian mountains, has devoted two of his most recent books to explorations of God and religion. Le Monde, the French establishment's newspaper of record, this year launched a glossy bimonthly "World of Religion."
"The need for meaning affects the secularized and de- ideologized West most of all," wrote Frédéric Lenoir, the editor of the new magazine, in his first editorial. "Ultramodern individuals mistrust religious institutions ... and they no longer believe in the radiant tomorrow promised by science and politics; they are still confronted, though, by the big questions about origins, suffering, and death."
Rocco Buttiglione, a confidant of the pope who was denied a bid to join the European Commission last year because of his staunch Catholic views on social issues, has a ready answer to such questions. "For a long time they told us that science and maths would give us the identity we need," he says. "Both failed. Now when Europeans ask themselves 'Who are we?' they don't have an answer. I suggest we are Christians."
That opinion is not widely shared. Critics point to the millions of immigrant Muslim Europeans living in France, Germany, Britain, and Spain, not to mention Europe's indigenous Muslims in the Balkans.
Nor are there many signs of a resurgence of organized religion on a continent where church attendance has been plummeting almost everywhere in recent decades.
Yet 74 percent of Europeans say they believe in a God, a spirit, or a life force, according to the latest findings of the European Values Study, a 30-year, Continentwide survey. And youth workers in Britain are finding "consistent evidence ... that a secular generation is being replaced by a generation much more interested in spiritual issues," says Stuart Murray-Williams, a theologian at Oxford University who recently published a book entitled "After Christendom."
A wide array of religious groups has sprung up across Europe to meet that generation's needs, most notably Buddhist communities.
"I've noticed a steady increase in interest," says Suvannavira, a Russian-born, British-educated monk who runs the Western Buddhist Order's Paris outpost in a cramped storefront meditation center. "Our order has doubled in size since 1990."
"The discourse has changed," Dr. Murray-Williams says. "Ten or 15 years ago, any mention of spiritual experiences would have drawn blank looks. Today people are hungry to talk about them." Murray-Williams says it's too soon to say what all this portends.
"There is a kind of inchoate spirituality that could be significant, or it could be a passing trend," he says. "It will be a while before we know whether or not it is strong enough to challenge the culture of secularism."
That culture is showing signs of wear, argues Jacques Delors, who once bemoaned Europe's lack of "soul" when he was president of the European Commission. "I fear that the construction of Europe is sinking into absolute materialism," he worries. "Things aren't going well for society, so society is little by little going to start asking itself what life is for, what death is, and what happens afterwards."
Some European politicians are picking up on that message. One with a particularly keen nose for the way the political wind is blowing is Nicolas Sarkozy, head of Jacques Chirac's conservative ruling party in France and a leading contender to be the country's next president.
"Politicians should not talk only about the economy, about social affairs, about the environment or security. We should also tackle spiritual questions," he said in a series of interviews published last November as a book, which has already sold 65,000 copies. "Religion's place in France at the beginning of the third millennium is central."
Suggesting that the state should subsidize churches and mosques - a radical break from the country's 100-year-old secular tradition - Mr. Sarkozy insists that he will "continue to argue for a new relationship between religions and the public authorities."
Sarkozy's novel approach, says Mr. Moisi, is based on "a sense that while for some, religion is the problem, it can also be part of the solution. He is bringing a kind of oxygen to the debate."
Mr. Buttiglione is bringing his own oxygen into that debate, devoting his time now to setting up a think tank and a popular movement to promote his beliefs. Traveling around most of Europe, he says, he has found "enormous interest" in his campaign "for a Christian presence in European politics."
The Vatican has launched itself actively into the fray as well, sending teams from Rome to rally the Spanish faithful against Prime Minister Jose Luis Rodriguez Zapatero's plans to legalize gay marriage, speaking out loudly in favor of Mr. Buttiglione, and lobbying hard for a reference to God in the European Constitution. [Editor's note: The original version of this article misstated the prime minister's title.]
Though the Catholic church lost that battle, it can take some consolation from Article 52 of the proposed Constitution, concerning the European Union's relationship with churches. "Recognizing their identity and their specific contribution," the article reads, "the Union shall maintain an open, transparent, and regular dialogue with these churches and organizations."
There is considerable scope, some religious leaders suggest, for those churches to unite in a bid to inject their common values into public life. After all, mainstream Christians, Jews, and Muslims share many views on family matters, and the sanctity of human life.
Indeed, some observers wonder whether the most significant "clash of civilizations" in Europe may pit, not Christians against Muslims, but believers of all faiths against nonbelievers.
There have been signs of such a development in recent months. The Archbishop of Paris, Cardinal Jean-Marie Lustiger, stood up for Muslims against the government's school ban on head scarves last year, for example, branding it an assault on religious freedom.
Similarly, both the Protestant and Catholic prelates in the English city of Birmingham showed understanding toward Sikhs who disrupted a theatrical performance last December.
The Sikhs were angered by the way the play, "Dishonour," written by a Sikh woman, included scenes of beatings, rape, and murder in a Sikh temple.
Several hundred of them stormed the Birmingham Repertory Theatre last December, causing management to halt the show and cancel all further performances for fear of unrest.
"Such a deliberate, even if fictional, violation of the sacred place of the Sikh religion demeans the sacred place of every religion," Vincent Nichols, the Catholic Archbishop of Birmingham wrote in a statement. "People of all faiths, therefore, will be offended."
It is unclear how many people were offended, because the rise in spirituality has not translated into growing support for organized churches, mosques or temples. Indeed, says Murray-Williams, the violence that has accompanied the eruption of religion into European public life "may exacerbate the difference between religion and spirituality.
"Many people see spirituality as something positive, while religion is seen as a system that can be divisive," he says.
But the signs are there, says Mr. Delors, to suggest that religious sentiment may yet take firmer hold in European life. "I don't expect a wholesale social mutation," he says. "But I can see little white stones marking out a path."
• Sophie Arie in Rome and Geoff Pingree in Madrid contributed to this report.