Razib says

a form of Islam which requires less marking off from the “kufar,” and implicit dominance of Muslim norms in the public space, can persist and flourish. Shared practices and values, broadly construed, is entirely compatible with starkly contradictory views on the nature of God, or the appropriate manner in which to worship God within religious establishments.

and I agree, though I do disagree with his larger premise in that I believe it’s precisely the multicultural tolerance he derides, and not a generalized “Protestantism”, which is the cultural foundation for America. The latter derives from the former, not the other way around.

Critics of multiculturalism like to mis-represent it as an orthodoxy unto itself, but its actually the absence of one. This is why America can be simultaneously deeply Protestantist and also the greatest Islamic country on Earth.