Religion plays too important a part in many people's lives to be denied a role in the public square. To be sure, there are some things the state can't do, like demand that schoolchildren pray each day. But elected officials, like other citizens, are free to have and express religious views. And voters are entitled to support or reject public officials for all kinds of reasons, including their religious views. To hold that elected officials can't publicly invoke their religion won't help a country of believers, agnostics and atheists reach any kind of consensus. It will only impoverish the conversation, depriving many citizens of the ability to make, and judge, arguments that reflect their most cherished views.