I think changes among Protestant denominations should be counted, by the way, because the movement has usually been from old, "mainstream" denominations--such as the Episcopal and Lutheran churches--to evangelical congregations. The ascendancy of evangelicalism over more liberal mainline Protestantism is one of the major religious and political stories of the past few decades. One of the more interesting findings is that one out of three Americans raised in the Roman Catholic Church--bad news for the pope and bishops--no longer considers himself or herself a Catholic.

The relative ease with which Americans cast off one spiritual identity for another is an old phenomenon; the Pew findings show only that there has been an expansion and acceleration of a longtime, perhaps inevitable, trend in a pluralistic society. Our secular Constitution provided the underpining for the fluid American religious landscape.Try as they might--and religious denominations certainly did in the past--the legal foundation of American society upheld the right of citizens to choose their own religion. Your priest, rabbi, or parents might be furious if you stepped outside the fold, but American society as a whole didn't care.

Intermarriage--and rates of intermarriage across ethnic, racial and religious lines are rising dramatically---is arguably the most important factor in conversions from one religion to another. Most of these changes in religion have nothing to do with spiritual awakening and everything to do with convenience and marital peace. Most conversions from Christianity to Judaism, for example, involve non-Jewish women who have married Jewish men. Have these women suddenly undergone a spiritual revelation? I doubt it. They convert because it's important either to their husband, or the husband's family, that the children be raised as Jews--and the mother must be Jewish for the child to be accepted as a Jew by religious authorities. Non-Jewish men married to Jewish women do not need to convert for their children to be considered Jewish under Jewish law--if one cares about such things.

I come from a long line of what I would call "converts of convenience." My maternal grandmother, the child of a German Lutheran immigrant, converted to Roman Catholicism when she married my Irish Catholic grandfather in 1919. She did it, as she told me explicitly, because it was important to her husband's mother that he marry a Catholic. "Why not?" she said. "It's the same God. I didn't care whether I was married by a priest or a minister, but his family did." A generation later, my mother--who was of course raised as a Catholic--married a non-practicing Jew, my father Robert Jacoby. Dad came from a family that was ashamed of being Jewish, and he was afraid my grandparents would oppose the marriage once they found out his "shameful" secret. My grandfather's response: "Bob, I thought you were going to tell us you'd been in jail or already had a wife." Dad himself converted to Catholicism eight years later, for a variety of reasons that also had nothing to do with religious fervor.. (For those of you who are interested, my memoir, Half-Jew: A Daughter's Search for Her Family's Buried Past (2000) is available on many used book Web sites. My father's two siblings also married Irish Catholics (an unusual choice for German Jews) and also converted to Catholicism.
My great-uncle Harold had married an Episcopalian (a more conventional choice for German Jews) at the turn of the twentieth century and he too converted. All of this had much more to do with the family's shame about being Jewish than about any real belief in Christianity.

America has always been a nation that offered extraordinary possibilities for reinvention; religious reinvention is one of those possibilities. From the standpoint of denominations being abandoned, this is certainly a weakness. The Catholic Church could count on no help from American society when people started abandoning it because of its stands on birth control, divorce, and a celibate male priesthood. Most rabbis still refuse to participate in ecumenical marriage ceremonies because they know that every intermarriage weakens traditional Judaism. Paradoxically, the ease with which Americans change religious identities may account for the excessive respect with which religion in general is regarded in this country.

In general, the Pew findings strongly support the idea advanced by Alan Wolfe, director of the Boisi Center for Religion and Public Life at Boston College, that American religion can be characterized as "broad but shallow." We have a minority of devout right-wing fundamentalists who have exercised political influence out of proportion to their numbers, and a minority of secularists who exercise less political influence than their numbers merit. In between there is a broad America that believes in God and respects religion in general but is not strongly committed to exclusionary religious principles or to a closer relationship between religion and government. There are also huge numbers of Americans who describe themselves as "spiritual but not religious"--a phrase I take to mean that they are hedging their bets by believing in some sort of divine providence but are not interested in undertaking the obligations that adhere to traditional religion. These are not people who want to get up for temple on Saturday or church on Sunday morning, but they like to watch television shows about angels and teenagers who talk to God.

I wish that the large number of Americans who are unaffiliated with any particular religion would think seriously about secularism and atheism. One great problem for those of us who are dismayed by the denigration of America's secular governmental traditions is that the wishy-washy "I'm-spiritual-but-not-religious" crowd never really engages in efforts to combat the harmful influence of right-wing religion in public life. Perhaps these people are too busy meditating to realize that the erosion of our cherished separation of church and state threatens their freedom as well as everyone else's.