The Park51 controversy is bound to blow up now that President Obama has weighed in. I've written a lot on the substance of it. The only new argument I've seen recently comes from Rick Hertzberg, who explains why the Auschwitz-Nun incident cited by the ADL and other opponents of Park51 doesn't hold water:

1. The convent at Auschwitz was to be a purely Catholic institution, with none of the interfaith aspects or broad community-serving purposes that mark the Park51 project.
2. In their fundraising appeal, the convent’s sponsors
described the convent as “a spiritual fortress and a guarantee of the conversion of strayed brothers from our countries as well as proof of our desire to erase outrages so often done to the Vicar of Christ."
Whether or not “the strayed brothers” requiring “conversion” is a reference to Jews—it might refer to fallen-away Catholics—it’s hard to interpret the reference to “outrages” supposedly perpetrated against the “Vicar of Christ” as anything other than an allusion to the well-documented charges that Pope Pius XII was, shall we say, less than fully engaged in trying to prevent the Nazi slaughter of the Jews of Europe.

Plus, of  course, the fact that the Auschwitz convent was proposed on location at Auschwitz, while Park51 is two blocks away. Also, credit to former Bush speechwriter Michael Gerson, who is one of the very few Republicans taking a liberal and strategically shrewd position here:

"An enormously complex and emotional issue -- but ultimately the right thing to do. A president is president for every citizen, including every Muslim citizen. Obama is correct that the way to marginalize radicalism is to respect the best traditions of Islam and protect the religious liberty of Muslim Americans. It is radicals who imagine an American war on Islam. But our conflict is with the radicals alone.”

As for the politics, it can't help Obama in the short run. This is a 70-30 issue and he's siding with the 30 -- and various right-wing loons have already been tying him to some imagined Islamic past for a couple years now.

On the other hand, I think this will pay long-term political dividends for Democrats. There's a classic pattern of Democrats cementing the allegience of minority groups by standing up for them when those groups sit outside the mainstream culture, and thus when there's a real political price to defending them. Fifty years from now, Muslims will be voting heavily Democratic because they'll remember that Obama defended their rights when it was unpopular to do so. Of course that won't help Obama, but it's impressive to see him stand on principle. Bush could have taken this position without suffering politically. Obama doesn't have that luxury.