Nothing could expose the loony left mind-set better than their reaction to Obama's decision to allow Rick Warren to offer up a prayer at his inauguration. A good summary is given here.
This snippet really sums up the situation, in all likelihood.
"I've left aside that they shouldn't really even have a religious invocation at the inaugural because it's become a tradition now. But my friend Capt. Fogg left an excellent comment that I urge to read in full. The main point being, "Religious rituals have no place at all in government. It's the law. Belief in God or gods is not part of public policy: that's the law, and if no religious test may be imposed for office, which is the law, why then are we asking a president to demonstrate his private religiosity in public, as part of his inauguration?"