James Oakes argues that when America was founded as a nation, it was overall much more secular than people today realize — and that the American government was established as a reflection of secular values:
In the year 1700, in the thirteen colonies, there was one church for every 598 colonists. Forty years later there was one church for every 642 colonists. And by 1780, in the middle of the War for Independence, there was one church for every 807 Americans. To put the matter simply, over the course of the eighteenth century the number of churches was declining in proportion to the number of Americans. 1780 was the lowpoint.
Here are some more numbers. In 1730 just under half (48%) of all the titles published in the colonies were religious. Religious titles dropped to 38 percent in 1760. The slide continued until it bottomed out in 1775, where a mere 16 % of all the titles published in the colonies were religious .
Not only was America relatively secular at the time, but it was growing more secular in the run up to the Revolution. It's not as though religious belief had absolutely no influence on the Revolution, but they clearly had relatively little influence in comparison to basic Enlightenment ideals which ranged from merely secular to outright anti-religious.
Oakes argues that in the course of the "Great Awakening," strict Calvinism was rejected and the status of clergy declined sharply. As a consequence, people started to believe that they could use their own powers of reasoning to arrive at truth and moral principles. Both our powers of reasoning and moral sense may have been originally created by god, but the fact remains that basic Christian beliefs were becoming secularized.
The wave of evangelicalism that swept the United States beginning in the 1790s was not really a "second" Great Awaking at all. It was not a continuation of the earlier failure. It was something else. What, precisely? Well, nothing "precisely," but a lot of things. And one of the things that evangelicalism was in the "New Nation," I suggest, was a reactionary assault on the secular humanism of the Revolution.
It still is.
Yes, the reactionary assault on the secular humanism, the secular principles, and the secular values that produced the American Revolution, the Declaration of Independence, and the Constitution continue down through today.