The issue arises with Massachusetts Gov. Mitt Romney's as-yet-undeclared bid for the 2008 Republican nomination. Romney would not be the first member of the Church of Jesus Christ of Latter-day Saints to run for the nation's highest office. He follows Orrin Hatch (2000); Mo Udall (1976); his father, George Romney (1968); and not least of all Joseph Smith, who ran in 1844 on a platform of "theodemocracy," abolition, and cutting congressional pay. Despite a strong showing in the Nauvoo straw poll, Smith didn't play much better nationally than Hatch did, and had to settle for the Mormon-elected post of King of the Kingdom of Heaven.

With his experience as a successful businessman, Olympic organizer, and governor, Romney has a better chance, but he may still have to overcome a tall religious hurdle. According to a recent Rasmussen poll, only 38 percent of Americans say they'd definitely consider voting for a Mormon for president. Yet many analysts think LDS membership is not an insuperable obstacle. Various evangelical sects continue to view Mormonism as heretical, non-Christian, or even satanic. But because of their shared faith in social conservatism, evangelical leaders seem open to supporting Romney. As far apart as they are theologically, Mormons and evangelical Christians may have more in common with each other anthropologically than they do with secular Americans watching Big Love on HBO. The remaining skepticism on the far right seems to have more to do with doubt about whether Romney has truly and forever ditched his previously expressed moderate views on abortion and gay rights.

But if he gets anywhere in the primaries, Romney's religion will become an issue with moderate and secular voters—and rightly so. Objecting to someone because of his religious beliefs is not the same thing as prejudice based on religious heritage, race, or gender. Not applying a religious test for public office, means that people of all faiths are allowed to run—not that views about God, creation, and the moral order are inadmissible for political debate. In George W. Bush's case, the public paid far too little attention to the role of religion in his thinking. Many voters failed to appreciate that while Bush's religious beliefs may be moderate Methodist ones, he was someone who relied on his faith immoderately, as an alternative to rational understanding of complex issues.

Nor is it chauvinistic to say that certain religious views should be deal breakers in and of themselves. There are millions of religious Americans who would never vote for an atheist for president, because they believe that faith is necessary to lead the country. Others, myself included, would not, under most imaginable circumstances, vote for a fanatic or fundamentalist—a Hassidic Jew who regards Rabbi Menachem Schneerson as the Messiah, a Christian literalist who thinks that the Earth is less than 7,000 years old, or a Scientologist who thinks it is haunted by the souls of space aliens sent by the evil lord Xenu. Such views are disqualifying because they're dogmatic, irrational, and absurd. By holding them, someone indicates a basic failure to think for himself or see the world as it is.

By the same token, I wouldn't vote for someone who truly believed in the founding whoppers of Mormonism. The LDS church holds that Joseph Smith, directed by the angel Moroni, unearthed a book of golden plates buried in a hillside in Western New York in 1827. The plates were inscribed in "reformed" Egyptian hieroglyphics—a nonexistent version of the ancient language that had yet to be decoded. If you don't know the story, it's worth spending some time with Fawn Brodie's wonderful biography No Man Knows My History. Smith was able to dictate his "translation" of the Book of Mormon first by looking through diamond-encrusted decoder glasses and then by burying his face in a hat with a brown rock at the bottom of it. He was an obvious con man. Romney has every right to believe in con men, but I want to know if he does, and if so, I don't want him running the country.

One may object that all religious beliefs are irrational—what's the difference between Smith's "seer stone" and the virgin birth or the parting of the Red Sea? But Mormonism is different because it is based on such a transparent and recent fraud. It's Scientology plus 125 years. Perhaps Christianity and Judaism are merely more venerable and poetic versions of the same. But a few eons makes a big difference. The world's greater religions have had time to splinter, moderate, and turn their myths into metaphor. The Church of Latter-day Saints is expanding rapidly and liberalizing in various ways, but it remains fundamentally an orthodox creed with no visible reform wing.