For any American serious about presidential elections, the very idea that one of the two major political parties has a large faction for whom religion is a major factor in determing the party's nominee should be frightening. But it's more than an idea. Fully one in seven likely voters in the Iowa caucuses believe that Mitt Romney's religion is a major reason to oppose him. Now, we can go on and on about how there should be no religious litmus test for president, in any party. But there is. In the GOP, Mormons, Muslims, and Jews need not apply (I know, Jews have not expressly been excluded the way Mormons and Muslims appear to have been, but name me one prominent Republican Jew who has run for president in modern history. Right...there are none. Nope, not even that guy.).
Let's not exclude the Democrats either. More than one Democrat has had to take to the airwaves to discuss his religion while running a presidential campaign. But let's be clear: neither Kennedy nor Obama had to do that as a prerequisite by progressive members of their party. Kennedy's West Virginia speech about his Catholicism was done to win over the very conservative Democratic voters in that state (voters whose descendants are now, by and large, Republicans). Obama's speech about his religion was to dispel the notion promulgated by Christianist Republicans that he was not a Muslim. To this day, people still believe he was lying.
The most dangerous thing we can do, as Americans, is to use religion as a criterion to pick a president. When we do that, we trash our Constitution and we trash the vision of our founders to erect a wall of separation between church and state.
Next time you meet a politician -- at any level, local or national -- tell him/her flat out that you don't care at all what his/her religion is, and that you will see that he/she is held accountable anytime he/she invokes religion as a way to attract votes.