Some of us have often wondered why it is that when Jerry Falwell urges his flock to vote Republican he is engaging in an unconstitutional breach of Church/State separation, but when Jesse Jackson urges black parishioners to vote Democrat he's standing in the best tradition of African American preachers. Creationists are accused of illicitly trying to impose a religious point of view on students by suggesting that metaphysical naturalism may not be true, but Darwinians who tacitly advocate metaphysical naturalism are not. It seems that religion in the public square is just fine as long as it's used to reinforce the liberal side in the culture war, but not if it is invoked by conservatives. Thus Bill Clinton's religious affirmations were never seen as a threat to the health of American politics, but George Bush's are.
Even granting that religion should have a legitimate place in our public life, however, there is a right way and a wrong way to express it. Steve Waldman has some interesting thoughts on this at National Review Online He writes:
Waldman is right. Unless people can argue from mutually shared assumptions they'll just be talking past each other. Thus Christians may hold to a particular belief primarily for religious reasons, but unless they can find non-religious premises from which to advocate their beliefs they'll be unpersuasive to people who don't share their religious worldview. If Christians wish to be effective players in the public arena they have to learn to meet those with whom they disagree on their opponent's turf.
In other words, every big game for the Christian has to be an away game. The only time they can play at home is when they debate each other. If they insist on engaging non-Christians on their own field by quoting Scripture, etc. they're going to find that nobody is going to show up for the game.