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PARIS - United States politicians wear their religion on their sleeve, but for their counterparts in France, faith is a private affair. Those tempted to make it a public one sense a risk akin to touching the third rail in the Paris Metro - it's potentially lethal for their careers.
For more than a century, secularism has ruled France's roost. The motto of the French Republic is "Liberty, Equality and Fraternity," rather than the Queen's "Dieu et Mon Droit" and the greenback's "In God We Trust".
In town halls, the figure of Marianne, the female symbol of the French state, reigns supreme - indeed, one technically cannot get married under French civil law unless the room has her bust. In state schools, government offices, courtrooms and other branches of the Republic, references to deities and religious symbols, from crosses to Muslim headscarves, are outlawed.
Separation of religion from state was enshrined in a 1905 law and the policing of it has, if anything, become even fiercer in recent years as the country fears a rise of Islamic fanaticism among its Arab minority.
To its defenders, strong secularism creates a zone of tolerance and neutrality for all citizens and provides an arena for the advancement of Muslim women in particular.
So President Nicolas Sarkozy has taken a major gamble by suggesting that the defence of secularism has at times bordered on intolerance, urging France to acknowledge its "Christian roots" and calling for faith be given a greater role in French life.
In a speech during the four-day visit to France by Pope Benedict XVI, Sarkozy took aim at anti-clericalism - hostility towards Catholic institutions and doctrine, a strand dating back to the 1789 Revolution - and said religion provided spiritual comfort lacking in society today.
"Religions, particularly the Christian religion with which we share a long history, are living heritages of reflection and thought, not just about God, but also about this core concern today about nature and the defence of the environment. It would be madness to deprive ourselves of it, quite simply a mistake against culture and thought," said Sarkozy.
Sarkozy said he wanted "positive secularism ... secularism which stages a dialogue, not a secularism which walls out or criticises".
He went further, implying that faith assuages the angst of modern life.
"In an era when doubt and withdrawal challenge our democracies to answer the problems of our time," said Sarkozy, "positive secularism offers our consciousness the means of an exchange, going beyond belief and rites, on the meaning that we want to give our existence - the quest for meaning."
Sarkozy's speech was warmly welcomed by the Pope. "New reflection on the true meaning and importance of secularism has become necessary," the Pontiff said, stressing though: "The Church does not want to take the place of the State. It does not want to replace it."
Liberal and left-wing critics poured vitriol over Sarkozy, while members of his own conservatives, the Union for a Popular Majority (UMP) party, were aghast.
"It's not for the president to tell citizens that without religion, nothing is possible," said Socialist MP Manuel Vals, author of a book on secularism.
"He has the right to his personal beliefs, but he cannot say, 'It would be madness to deprive ourselves of religion'. Not only is this wrong and dangerous, it is also abuse of office. His job is not to be a philosopher or a pastor, but simply to uphold secularism."
"Mixing religion and politics is neither good for the Republic, nor good for religion," said Francois Bayrou, a committed Christian and secularist who heads the liberal Modem party.
Francois Baroin, a UMP legislator and former interior minister, took aim at Sarkozy. "Secularism is neither positive nor negative, it's an absolute value and a rule for communal life," he said. But he doubted that the president intended any weakening of the key 1905 law.
Others, though, said Sarkozy was right to touch on aggressive forms of secularism and to evoke the yearning of people to fill a spiritual void.
"Reason is the basis of our society. But it also has its limits. Unless it makes the argument that human life is absurd, it also has to address faith," said historian Max Gallo.
Liberal Catholic writer Christian Terras said Sarkozy was gingerly trying to carry out a "diametrical" shift compared to his predecessors.
Terras attributed the shift to Sarkozy's admiration for the US, where religious zeal co-existed side by side with tolerance. But, he warned, to try to carve out a greater role for faith in France could badly backfire.
"It's a double-edged sword. If the Church takes a greater role, it could fuel a form of anti-clericalism which has largely dissipated because secularism has been such a success.
"Indeed, secularism has even become a constitutional model elsewhere in the world where there are ethnic or religious conflicts, such as in Bosnia."
