There is perhaps no subject more taboo among American elites than religion. You can mention sex and get away with it. Money is almost respectable. Politics necessary. Family interesting. But if you want to break up a dinner party, upset a fellow worker or lose respect among your enlightened friends, the sure-fire way to do it is to confess that you are religious.

By religious, I mean that you take religious faith seriously, read spiritual writers, attend services regularly, hold that religious faith should in part determine political opinions. This is the heresy in the religion of secularism. If you want to provoke a near-riot, get specific: Mention the resurrection of Christ, life after death, the teachings of the Torah, the certainty of reincarnation.When conservatives claim that the East Coast elite is irredeemably "liberal" and therefore untrustworthy, they are therefore only half right. The real truth - and in his book "Under God: Religion and American Politics" Garry Wills comes to the brink of uttering it - is that the elite is overwhelmingly irreligious, and that this is the source of the great gulf in political and moral culture between it and the American masses.

Wills' treatise is essentially a campaign book, centered imaginatively around this theme. He notes that the 1988 campaign was - on the surface at least - as secular as most others, but that the rhetoric and symbolism was deeply religious. He observes that two of the most interesting candidates, Jesse Jackson and Pat Robertson, were preachers and that their appeal and rhetoric was based in the American religious experience. He suggests that religion is the key to understanding the entire campaign.

A key part of this argument rests on Michael Dukakis' ambivalence about the pledge of allegiance. Wills says that it had roots in previous controversies about the interpolation of "under God" into the pledge and tapped into the long-running American battle about the separation of church and state. What the issue reflected, he argues, was a genuine and deep schism in American opinion between secular elites and religious masses. George Bush, the quintessential establishment WASP, successfully maneuvered himself on the side of the religious masses and secured a critical advantage over the hapless Dukakis.

What this implies, of course, is that the Bush campaign was not a mere exercise in mud-slinging. Bush was pointing out something true about Dukakis: that he didn't have a religious bone in his body, and this was a legitimate concern for a deeply religious electorate. Bush's religiosity was almost as suspect, of course, but his sin in exploiting the issue was hypocrisy, not sleaziness.

Where Wills is less convincing is in the lesson he draws from all of this: that the Democrats need to marshal the religious vision of a Jesse Jackson in order to win again. To be sure, they need a religious sensibility less obviously fake than Mario Cuomo's. (Wills' dissection of Cuomo's intellectually phony stance on abortion is one of the highlights of the book.) But Wills seems blind to the extent to which Jackson is a parasite on genuine religious experience rather than its most articulate defender. Jackson's switch on abortion - marginally less convincing than Bush's switch the other way - is just one example of this. The notion that Jackson is a genuinely spiritual leader is far-fetched.

And Wills' belief that the coalition of interest groups that defeated the nomination of Robert Bork to the Supreme Court is the key to this new religious vision is even more unconvincing. They engaged in some of the most blatant distortion in recent memory, and many have as their primary aim a constitutional attack on American public religiosity. It's hard to see how they are not part of the Democrats' problem, rather than a solution to it.

That said, this is an enormously readable and stimulating collection of essays. There is a fascinating digression into the religious faith of Thomas Jefferson and a superb portrait of the evangelical Francis Schaeffer. Wills provides an interesting, if to my mind unconvincing, argument about the limits to public pornography, and a smart defense of abortion rights from a religious perspective.

He lends credence to the ancient view that human life begins at "quickening" - that time in the life of an unborn child when it tangibly seems to have an existence of its own. Wills further argues that doubt itself about the status of the fetus should lead us to prefer the moral person of the mother over that of the dubious child in any debate about the rights of each. But it is not clear why doubt about whether the fetus is a human being should not equally lead one to protect the fetus just in case human life is at stake. Catholics who are already inclined to defend the pro-choice position would do well to digest his musings. Others will remain, I suspect, unpersuaded.

If there is a fault in this book, it lies in Wills' temptation to wear his learning ostentatiously, as if a Jesuit education and an ability to read Latin were by themselves qualifications for contemporary cultural criticism. And the subject of the book - religion and American politics - is too broad for these eclectic musings to satisfy fully. But Wills has broken the religious taboo - and done so readably and highly intelligently. May more religious writers and thinkers follow in his wake.