The April 14, 2008 issue of The New Yorker has a review by Jill Lepore of a pile of books on religion and politics in US history, especially having to do with the founding constitutional separation of church and state. The books are:

• Forrest Church, So Help Me God: The Founding Fathers and the First Great Battle Over Church and State (Harcourt)
• Frank Lambert, Religion in American Politics: A Short History (Princeton University Press)
• Martha Nussbaum, Liberty of Conscience: In Defense of America's Tradition of Religious Equality (Basic Books)
• Steven Waldman, Founding Faith: Providence, Politics, and the Birth of Religious Freedom in America (Random House)
• Garry Wills, Head and Heart: American Christianities (Penguin Books)

Lambert's book only makes a brief appearance before Lepore settles into her subtitle, "Did the Founders want us to be faithful to their faith?" (p. 73):

It's probably impossible to discover precisely what the Founders believed about God, Jesus, sin, the Bible, churches, and Hell. They changed their minds and gave different accounts to different people: Franklin said one thing to his sister Jane, and another thing to David Hume; Washington was a vestryman at his church, but, as he lay slowly dying, he never called for a clergyman. This can make them look like hypocrites, but that's unfair. THey approached religion in more or less the same way that they approached everything else that interested them: Franklin invented his own; Washington proved diplomatic; Adams grumbled about it; Jefferson could not stop tinkering with it; and Madison defended, as a natural right, the free exercise of it.

Referring to Waldman, Church, Nussbaum, and Wills ("very different books . . . but each, striving for evenhandedness, wants to save us from the errors of partisans and zealots") (pp. 73-74):

The four books achieve a kind of consensus in four related lines of argument. First, the Unitd States was founded neither as a Christian nation nor as a secular one. Second, by the standards of Evangelicals of both their day and ours, Franklin, Washington, Adams, Jefferson, and Madison were not Christians; they wrestled, often profoundly, with religious questions, but, as Church points out, "they all doubted the divinity of Christ." Third, the disestablishment of religion is itself responsible for Americans' unusual religiosity, which (these writers all believe) is something to celebrate. Fourth, notwithstanding the Founders' own remarkable secularism, the liberation of religion from government as much as the reverse was their aim. "The separation of church and state has greatly benefited religion, as Madison and Jefferson predicted that it would," Wills writes. Nussbaum argues that because "the separation of church and state is, fundamentally, about equality, about the idea that no religion will be set up as the religion of our nation," in the end "separation is also about protecting religion." Waldman writes, "Madison, I suspect, would . . . be delighted by surveys showing that, compared with most developed nations, Americans believe in God more, pray more, and attend worship services more frequently."

Much of the review concerns Royall Tyler, a poet and lawyer who once dated John Adams' daughter, and wrote a novel which made some reference to Islam (pp. 74-75):

In June of 1797, just three months before Tyler's novel was published, the American captives in North Africa were freed by the Treaty of Tripoli, signed by President John Adams. The threaty's Article 11, an assurance that the United States would not engage in a vengeful holy war, read, "As the Government of the United States of America is not, in any sense, founded on the Christian Religion; as it has in itself no character of enmity against the laws, religion, or tranquillity, of Mussulmen; and, as the said States never have entered into any war or act of hostility against any Mahometan nation it is declared by the parties that no pretext arising from religious opinions, shall ever produce an interruption of the harmony existing between the two countries."

I guess we can chalk that up as yet another aspect in which the Bush administration has strayed from republic's founders.