That was a question raised by, of all people, the Norwegian terrorist Anders Breivik, and it seemed to me to highlight the phenomenon of believers like Pope Benedict joining with atheists like Italian politician-philosopher Marcello Pera to promote a cultural Christendom -- but with Christianity itself optional.From my RNS story:

"European Christendom and the cross will be the symbol in which every cultural conservative can unite under in our common defense," Breivik wrote in his rambling 1,500-page manifesto. "It should serve as the uniting symbol for all Europeans whether they are agnostic or atheists."Whether Breivik himself can be considered a bona fide Christian given his lack of a "personal relationship with Jesus Christ and God," as he put it, was a topic of much debate. There was no doubt, however, that he was a devout believer "in Christianity as a cultural, social, identity and moral platform."In fact, that's been the case for any number of unbelievers for more than a decade.One prominent example was the Italian journalist Oriana Fallaci, who spent her last years before her death in 2006 inveighing against a Muslim influx that was turning the continent into what she called "Eurabia."Fallaci liked to describe herself as a "Christian atheist" -- an interesting turn of phrase -- because she thought Christianity provided Europe with a cultural and intellectual bulwark against Islam.There's also Scottish-born historian and political conservative Niall Ferguson, who calls himself "an incurable atheist" but is also avocal champion for restoring Christendom because, as he puts it, there isn't sufficient "religious resistance" in the West to radical Islam.(Ferguson dedicated his latest book, "Civilization: The West and the Rest," to his new partner, Ayaan Hirsi Ali, the Somali-born Dutch atheist who has promoted the values of Christianity over those of her native Islam.)The modern-day crusade for Christendom by nonbelievers tends to be rooted in fears about Muslim immigration, but it's also fueled by worries about the deterioration of European culture -- and nostalgia for the continent's once central place in world affairs.For some atheists, retaining European identity is reason enough to set aside long-standing enmity between churches and nonbelievers that dates back to the secularism of the Enlightenment and the anti-clericalism of the French Revolution.And unlike the persistent sniping between atheists and believers in the U.S., Europe's nonreligious conservatives have found ready allies in the continent's religious leaders -- most notably Pope Benedict XVI.

All that, plus Pascal's Wager, here.