Some American history, from Citizen Magazine (emphasis in original):
…Today, there are some — mainly on the Left — who paint the Founders not as Christians but as Deists, believers in an impersonal creator who left his creations to fend for themselves. But while that description fits less than a handful of the Founders, to varying degrees, it clearly doesn’t fit the vast majority.
Of the 55 signers of the U.S. Constitution, “with no more than five exceptions, they were orthodox members of one of the established congregations,” wrote the late University of Dallas historian M.E. Bradford.6 “References made by the Framers to Jesus Christ as Redeemer and Son of God … are commonplace in their private papers, correspondence and public remarks — and in the early records of their lives.”7
And this wasn’t just lip service, Bradford noted: The faith the Framers professed played a large role in their lives.
Thus, both James Madison and Alexander Hamilton “regularly led their households in the observance of family prayers.” Roger Sherman “was a ruling elder of his church.” John Dickinson of Delaware “wrote persuasive letters to youthful friends conserving the authority of Scripture and the soundness of Christian evidences.” Richard Bassett, also of Delaware, “rode joyfully with his former slaves to share in the enthusiasm of their singing on the way to Methodist camp meetings.” Elias Boudinot of New Jersey “was heavily involved in Christian missions and was the founder of the American Bible Society.” 8
The Wall That Never Was
Why would such men have written a First Amendment that sought to purge religious expression and values from the public square? Simple: They didn’t.The Founders wanted to preserve the many vibrant Christian churches that were thriving in America. So they provided in the First Amendment that no Congress could squelch the free exercise of religion or establish a national church body— as had happened in England, driving many of their ancestors to the New World.
They also created a decentralized system that left states free to pursue diverse policies. Some (New Hampshire, Massachusetts, Connecticut, South Carolina and Maryland) gave funding or property to churches. A few state constitutions contained religious requirements. Pennsylvania and New York required officeholders to pledge belief in the divine inspiration of Scripture.
To be sure, that wasn’t the norm. Most states guaranteed religious liberty, on the principle that government compulsion was an affront to true worship. But the very language in those guarantees testified to the prevailing faith. Many used terms of praise like “Almighty God.” Massachusetts spoke of “the right, as well as the duty, of all men in society … to worship the Supreme Being, the great Creator and Preserver of the universe.”9
And the federal government itself, though much more limited in its religious involvements, did things that would make an ACLU attorney blanch. Even one of the least religiously orthodox Founders, Thomas Jefferson, used federal funds during his presidency to build churches and to support Christian missionaries working among the Indians.
That’s especially meaningful since it was Jefferson who authored the phrase “wall of separation between church and state” in a letter to the Danbury (Conn.) Baptist Association — words now commonly misused to claim that the Founders would have supported an ACLU-like approach. But as Dreisbach notes, “The absurd conclusion that countless courts and commentators would have us reach is that Jefferson routinely pursued policies that violated his own ‘wall of separation.’ ”10
In truth, the Founders never dreamed that, one day, the government they helped establish would so often be hostile to the faith that most of them — despite their many other differences — held in common…
I was raised with the ‘founders were Deists’ idea pounded into my head again and again, which suited me fine (at first) since I was bouncing around from agnostic to atheist to deist myself – and since I was historically illiterate. But then I found more of the old documents, and contemporary accounts of the American Revolution and the decades before and after it. Thinking that the religious tone and references showed a different story than the one I was being told, I asked a teacher or two about it. I was then assured that the Founders wrote and talked that way because the masses were so ignorant as to still believe all that God garbage, and our Founders were wise enough to humor them.
Then I discovered letters that they wrote to each other, and to young people they were mentoring. So much for that ‘humoring the masses’ idea. Upon hearing this objection, my teachers told me that although the Founders were products of the Enlightenment, they were of course early in the process and so were of course poisoned by the social conventions of their times. They didn’t really believe in God, they simply didn’t know how to talk or write or think any other way…
Uh, huh.
While I will agree that we are all influenced by the culture in which we are raised (witness the fact that I actually believed my teachers for a while, even on that last point), at some point I had to decide that my teachers were protesting too much. The Founders – who pledged their lives, fortunes, and sacred honor for the cause, and stayed the course at tremendous sacrifice, and who prayed and praised God both publicly and privately – made sense only if I ignored the very odd, and very recent, spin put upon them by my teachers. The original documents, the earlier textbooks, the art around official buildings in Washington D.C., the policies of the government – pretty much everything put out by people who hadn’t fallen into Social Darwinist thinking (or its near cousins) – argued against the intellectual fad I was taught in public school, and then in college.

Separation of church and state is a bedrock principle of our Constitution much like the principles of separation of powers and checks and balances. In the Constitution, the founders did not simply say in so many words that there should be separation of powers and checks and balances; rather, they actually separated the powers of government among three branches and established checks and balances. Similarly, they did not merely say there should be separation of church and state; rather, they actually separated them by (1) establishing a secular government on the power of the people (not a deity), (2) saying nothing to connect that government to god(s) or religion, (3) saying nothing to give that government power over matters of god(s) or religion, and (4), indeed, saying nothing substantive about god(s) or religion at all except in a provision precluding any religious test for public office. They later buttressed this separation with the First Amendment, which constrains the government from undertaking to establish religion or prohibit individuals from freely exercising their religions. The basic principle, thus, rests on much more than just the First Amendment.
James Madison, who had a central role in drafting the Constitution and the First Amendment, confirmed that he understood them to “[s]trongly guard[] . . . the separation between Religion and Government.” Madison, Detached Memoranda (~1820). He made plain, too, that they guarded against more than just laws creating state sponsored churches or imposing a state religion. Mindful that even as new principles are proclaimed, old habits die hard and citizens and politicians could tend to entangle government and religion (e.g., “the appointment of chaplains to the two houses of Congress” and “for the army and navy” and “[r]eligious proclamations by the Executive recommending thanksgivings and fasts”), he considered the question whether these actions were “consistent with the Constitution, and with the pure principle of religious freedom” and responded: “In strictness the answer on both points must be in the negative. The Constitution of the United States forbids everything like an establishment of a national religion.”
Your focus on the religiosity of various founders and whether they were deists, Christians, and such is off target. Separation of church and state is not a concept born of deism, atheism, or some such. While the religious views of various founders are subjects of some uncertainty and controversy, it is safe to say that many founders were Christian of one sort or another. In assessing the nature of our government, though, care should be taken not to make too much of various founders’ individual religious beliefs. Their individual beliefs, while informative, are largely beside the point. Whatever their religions, they drafted a Constitution that establishes a secular government and separates it from religion as noted earlier. This is entirely consistent with the fact that some founders professed their religiosity and even their desire that Christianity remain the dominant religious influence in American society. Why? Because religious people who would like to see their religion flourish in society may well believe that separating religion and government will serve that end and, thus, in founding a government they may well intend to keep it separate from religion. It is entirely possible for thoroughly religious folk to found a secular government and keep it separate from religion. That, indeed, is just what the founders did.
It is instructive to recall that the Constitution’s separation of church and state reflected, at the federal level, a “disestablishment” political movement then sweeping the country. That political movement succeeded in disestablishing all state religions by the 1830s. (Side note: A political reaction to that movement gave us the term “antidisestablishmentarianism,” which amused some of us as kids.) It is worth noting, as well, that this disestablishment movement largely coincided with another movement, the Great Awakening. The people of the time saw separation of church and state as a boon, not a burden, to religion.
This sentiment was recorded by a famous observer of the American experiment: “On my arrival in the United States the religious aspect of the country was the first thing that struck my attention. . . . I questioned the members of all the different sects. . . . I found that they differed upon matters of detail alone, and that they all attributed the peaceful dominion of religion in their country mainly to the separation of church and state. I do not hesitate to affirm that during my stay in America, I did not meet a single individual, of the clergy or the laity, who was not of the same opinion on this point.” Alexis de Tocqueville, Democracy in America (1835).
The Constitution, including particularly the First Amendment, embodies the simple, just idea that each of us should be free to exercise his or her religious views without expecting that the government will endorse or promote those views and without fearing that the government will endorse or promote the religious views of others. By keeping government and religion separate, the establishment clause serves to protect the freedom of all to exercise their religion. Reasonable people may differ, of course, on how these principles should be applied in particular situations, but the principles are hardly to be doubted. Moreover, they are good, sound principles that should be nurtured and defended, not attacked. Efforts to undercut our secular government by somehow merging or infusing it with religion should be resisted by every patriot.
Wake Forest University recently published a short, objective Q&A primer on the current law of separation of church and state–as applied by the courts rather than as caricatured in the blogosphere. I commend it to you. http://tiny.cc/6nnnx
The Constitution is about limiting the reach of the federal government. It forbids a national denomination being imposed, like had been done in Europe, to the ruin of many. There was built into our system – both legal and in society – a tolerance of a wide variety of Christian worship and a respect for Jews, and protection of people who reject God but live peaceable, moral lives. What we’re seeing now is a replay of what they got away from – the government, largely through the courts this round, trying to force compliance with dictates that force citizens to choose whether they will be faithful to God or to the government.
While the First Amendment undoubtedly was intended to preclude the government from establishing a national religion as you note, that was hardly the limit of its intended scope. The first Congress debated and rejected just such a narrow provision (“no religion shall be established by law, nor shall the equal rights of conscience be infringed”) and ultimately chose the more broadly phrased prohibition now found in the Amendment. During his presidency, Madison vetoed two bills, neither of which would form a national religion or compel observance of any religion, on the ground that they were contrary to the establishment clause. While some in Congress expressed surprise that the Constitution prohibited Congress from incorporating a church in the town of Alexandria in the District of Columbia or granting land to a church in the Mississippi Territory, Congress upheld both vetoes. In keeping with the Amendment’s terms and legislative history and other evidence, the courts have wisely interpreted it to restrict the government from taking steps that could establish religion de facto as well as de jure. Were the Amendment interpreted merely to preclude government from enacting a statute formally establishing a state church, the intent of the Amendment could easily be circumvented by government doing all sorts of things to promote this or that religion–stopping just short of cutting a ribbon to open its new church.
The issue you raise about the government requiring or prohibiting something that conflicts with someone’s faith is entirely real, but not new. Nor is it unique to Christians–hardly. The courts have occasionally confronted such issues and have generally ruled that the government cannot enact laws specifically aimed at a particular religion (that would violate the First Amendment), but can enact laws generally applicable to everyone or at least broad classes of people (e.g., laws concerning traffic, pollution, taxes, contracts, fraud, negligence, crimes, discrimination, employment, and on and on) and can require everyone, including those who may object on religious grounds, to abide by them. Were it otherwise and anyone could opt out of this or that law with the excuse that their religion requires or allows it, the government and the rule of law could hardly operate. While the government has this power, it may (and sometimes does) choose to relieve individuals of this bind by including conscientious objector provisions or the like in the law.