The framers of the Constitution knew that if you allow organized religion to interfere with secular law, secular law can interfere in organized religion.
But Palin and others believe that the door only swings one way. And they're idiots for it.
Meanwhile, I give you James Madison, responsible for assembling the Constitution:
“Strongly guarded as is the separation between religion and & Gov’t in the Constitution of the United States the danger of encroachment by Ecclesiastical Bodies, may be illustrated by precedents already furnished in their short history.” (Detached Memoranda, circa 1820)
“Having always regarded the practical distinction between Religion and Civil Government as essential to the purity of both, and as guaranteed by the Constitution of the United States, I could not have otherwise discharged my duty on the occasion which presented itself.” (Letter to Baptist Churches in North Carolina, June 3, 1811)
These zealots need to spend some more time becoming familiar with the Enlightenment. The framers were products of the Enlightenment, as was the whole notion of America -- despite what fakers like Sarah Palin and Glenn Beck will tell you.