....In modern times, religion has become so intertwined in our political rhetoric that the failure of any president to invoke God in a speech as important as the inaugural could hardly escape notice. Thanks to this graphic in The Wall Street Journal, we noticed the presidents who did (nearly all) and the few who didn't (Teddy Roosevelt, Rutherford B. Hayes).

But the inaugural references to a Supreme Being have evolved over time, says Ann Duncan, an assistant professor of religion at Goucher College in Baltimore. For example, George Washington, John Adams, Thomas Jefferson, James Madison — all influenced by the deism that infused most of the American Revolution-era thinkers — never once mentioned God in their inaugurals.

For them, God was "a rather distant ... but still very providential and powerful force," Duncan says. "Not the kind of personal god that an evangelical Christian today might talk about."...
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Good read.

IMHO there is still too much of it in politics. I get the need to use it due to the fact that most Americans believe in some sort of god. I 'suppose the problems start when people start bickering over whose version of god is being referred to.