The Catholic and the atheist are about to square off in Canada in a debate that will address that very question:

In advance of the debate, the two men sat down with The Globe and Mail to discuss their views.

The surprises? Mr. Hitchens, who lives in Washington, D.C. has had a Christmas tree as long as he’s been a father and observes Passover. He discovered his family’s Jewish roots late in life; his wife, Carol Blue, is also Jewish.

And Mr. Blair’s father, Leo, a retired law professor, is a “militant atheist.” The long-time politician also revealed in his recently released memoir, A Journey: My Political Life, that he has always been more interested in religion than politics.

For Mr. Blair, who converted to Catholicism after leaving office in 2007, religion plays the most central of roles, both personally and in his worldview.

“I think the place of faith in the era of globalization is the single biggest issue of the 21st century,” he said in a hotel suite populated by several aides and security guards.

“In terms of how people live together, how we minimize the prospects of conflict and maximize the prospects of peace, the place of religion in our society today is essential. … I think religion could be, in an era of globalization, a civilizing force.”

For Mr. Hitchens, author of the best-selling God Is Not Great: How Religion Poisons Everything, religion has to be opposed for myriad reasons, including its “radical frontal attack on human dignity” in presuming that humans wouldn’t otherwise know right from wrong. He also calls proselytizing “a sign of intellectual and moral weakness.”

Read on.