(Freethinkers: A History of American Secularism; By Susan Jacoby; Holt, 417 pp.; $27.50 )
''Freethinkers" is a gutsy, passionate, intelligent book. It is also flawed, perhaps inevitably, by Susan Jacoby's attempt to deny the tautological dance between ideology and government. But if the author's beliefs at times frustrate her efforts to adjudicate fairly those of others, such a lapse in insight only demonstrates, in the end, her most important point. Too much is at stake in decisions that guide the polis to allow any faction of society to impose its own ideology based on religion as we commonly understand that word.
''For a democratic society . . . there must be a moral consensus, extending beyond and in some instances contradicting particular religious beliefs, to maintain the social contract," she intones early on, summing up the crux of her admirable argument.
Especially until she gets into the later 20th century, her analysis is strong, clear-sighted, and impassioned, escaping covert partisanship. Organized chronologically, ''Freethinkers" opens with John Adams and Thomas Jefferson's extraordinary achievements in establishing a strictly secular government for the new nation. For Jacoby, the image of the founders as ''devoutly religious men" is a vast oversimplification, an important mythology sustained by those who want to portray secularism as un-American.
Jacoby's discussion moves to the antislavery and women's suffrage movements, where she presents fairly religion's general role in those politics. But she tends to privilege speakers such as Elizabeth Cady Stanton for their atheism, even as she acknowledges Stanton's shocking sarcasm when she decries men so lowly as the ''Sambos" and ''Yung Tungs" who dare to make laws for the educated white women of her movement. And Jacoby barely touches upon important, often overlooked ''conventional" figures such as Temperance leader Frances Willard, who, a year before she died, announced firmly to an incredulous conservative women's group that she was and could only be a ''Christian Socialist."
The politics of religious faith create, as Jacoby posits, serious problems if not fought out on largely private grounds. Her discussion of Abraham Lincoln's struggle with the issue, and his own confusion over religious belief, is a forceful, unexpectedly poignant one. She reminds us that now largely forgotten heroes such as the agnostic Robert Green Ingersoll, more passionate and persevering in his beliefs than most, show us how to maintain a mutual respect for opponents.
On the other hand, I wish that I were persuaded by Jacoby's case for the political importance of one of our nation's most brilliant poets, Walt Whitman. I do find, however, in her praise of Whitman's prescient nonsexist language, a reminder of the blind spots in which we inevitably find ourselves. She approves Whitman's lines ''I am the poet of the woman the same as the man,/And I say it is as great to be a woman as to be a man." And she lauds his ''striking" use of ''men and women where other writers simply use 'man' to stand in for humanity." Throughout, however, Jacoby has invoked the old-fashioned ''man" to indicate both genders. I also wince at the too dull darts she throws at her opponents: ''zygotes even more foolish than the one who produced Lysenko [Stalin's biologist]." The problem is more than one of style: As with all such pronouncements, ideology, in this case smugness in the place of passion, runs roughshod over the inclusive and measured logic the author usually conveys.
Her subject is a massive one, and Jacoby was, no doubt, hard-pressed about what to include. The McCarthy era gets a good if brief once-over, especially useful when she reminds us how quickly the dangerous mix of religion and political convictions can blindside us in moments of national fear. The 1954 addition of the compulsory ''under God" to the Pledge of Allegiance was a reaction to ''Soviet godlessness," a phrase meant to distinguish our government from the atheist enemy.
But though she cites the ''crucial role of religion during the Red Scare of the fifties," Jacoby details it very little. And her subsequent compact treatment of the part that religion played in the civil rights movement seems disproportionate, given that period's complicated mix of church and state. In addition, her rationale for invoking the Jehovah's Witnesses while neglecting the Mormons as key political players begs for an explanation.
A vexing question yet remains: Are we wise to proceed as if we can address the needs of this nation without tapping into its essentially spiritual if contradictory resources? Jimmy Carter, faith-infused Southern Baptist nonpareil, was one of our most socially minded, secular presidents in recent times. Bill Clinton, churchgoer par excellence, knew about the Rwandan massacres and failed to act out of local political motivations; he signed the Defense of Marriage Act, which buoyed the prospects of gay marriage opponents. If George Bush frontloads his belief proudly for our review, are we sure we are not safer for that overbright spotlight?
The watchdog eye of the citizen is perhaps our best defense, including invaluable books such as Jacoby's. ''Freethinkers" is a must read for those interested in the ways our nation's most cherished traditions of freedom evolved -- and as a reminder of what is at stake in protecting that legacy.
Laura Claridge is the author of ''Norman Rockwell: A Life."