But the analysis should go even further. After all, if we are acknowledging America’s religious heritage, it only seems right that we should also consider the country's secular heritage. By assessing both heritages and comparing the two, we can gain some valuable perspective on the country and its history. Indeed, by conducting such an exercise we get an accurate undersanding of the true roles of both religion and secularity.

Enlightenment values: The philosophical foundation and inspiration for the American Revolution was the Enlightenment, which is a period noted for its religious skepticism and its appreciation of reason over . Known as the Age of Science, the Enlightenment spanned the late seventeenth and eighteenth centuries and was the first period in European history during which it was sometimes safe—in certain circles—to openly reject Christianity. Jefferson and other founders were greatly influenced by the Enlightenment writings of John Locke (1632-1704) and others, and their religious views were shaped in large part by the non-Christian, reason-based deism that was popular among educated men of the Enlightenment era.

Our non-Christian Founding Documents: Secularity permeates many of America’s key early documents. The Constitution is a God-free text, making no reference to any divine authority but instead vesting power in “We the People.” The only reference to religion in the original Constitution was a negative, a statement saying that there shall be no religious test for holding public office. As if that weren’t clear enough, less than a decade after the Constitution’s ratification the Senate unanimously approved the Treaty of Tripoli, which expressly stated that the young nation “was not in any sense founded upon the Christian religion.”

Religious conservatives sometimes point to the Declaration of Independence, which makes references to “Nature’s God” and rights that are endowed by a “Creator,” as evidence of serious religiosity on the part of the framers, but they overlook the distinctly non-Christian character of these references. “Nature’s God” and “Creator” were common deistic terms which, if anything, indicated an effort by the framers to distance themselves from Christianity and traditional theism. Considering that the document was written in the eighteenth century, such language can be understood as evidence of religious skepticism, not , and it is noteworthy that even these vague religious references were excluded when the Constitution was drafted a decade later.

In the article and slide show here, I point out that religious skeptics can be found doing great things throughout American history. Not all religious skeptics identify as atheists, of course, but that’s not the point, as secularity and skepticism can be expressed via means other than atheist identification. Jefferson was a deist but, for his time, was indeed a skeptic and man of reason. Figures such as Thomas Paine, Elizabeth Cady Stanton, Susan B. Anthony, Robert Ingersoll, Mark Twain, Clarence Darrow, Carl Sagan, A. Philip Randolph, and Pat Tillman comprise a noble history of American nonbelievers of various types. With a glance at the American Humanist Association's list of Humanists of the Year—with figures ranging from Jonas Salk to Margaret Sanger to Steven Pinker—one quickly sees that humanists have been great contributors to society for many years.

Secular Popular Culture: Though an open atheist is unlikely to go far in American today, once we leave the realm of politics we see nonbelievers highly visible in many other pockets of American culture. Entertainment, for example, is filled with high-profile figures who are open about their skepticism. Brad Pitt, Angelina Jolie, Penn Jillette, Jodi Foster, Katharine Hepburn, and innumerable others have made no secret of their rejection of theism. Some, such as Bill Maher and George Carlin, have made the criticism of traditional religion a cornerstone of their careers. The popularity of such artists demonstrates that Americans often rejoice in secularity, and surely our culture would be barren without its tradition of irreverent and blasphemous films, novels, music, and art. Despite the strange piety of our politics, our culture otherwise derives much satisfaction from the rejection of traditional theism.

It is worth noting that, unlike its religious heritage, America's secular heritage gives us little reason to cringe. Slavery was never justified based on the non-existence of God, nor were Quakers ever hanged on Boston Common to defend the purity of any secular doctrine. Of course, not all nonreligious Americans have been noble and admirable, and surely men and women who are personally secular have occasionally been guilty of poor judgment and bad taste, but no objective observer could conclude that America’s secular heritage, viewed in its totality, is anything but a proud and important aspect of the nation’s history, a tradition that reflects an appreciation of progress, reason, and critical thinking, one that is certainly as notable as any religious heritage.

In light of these facts, one must wonder why there is never any talk from politicians or the media of "acknowledging our secular heritage."

Nonbeliever Nation: The Rise of Secular Americans is David Niose's new book, just released by Palgrave Macmillan.