FWIW, the one thing I can agree with Sam Harris on is that European integration of muslims (and other minorities) is slow compared to the US because they have less of a commitment to freedom of speech. For all of our racial problems, the US does a better job of integrating immigrant communities because we have a culture of airing our dirty laundry, of hashing out our feelings - bigotry and all - and thus working through the differences rather than sheltering people from possibly being offended. Its ugly and frequently unpleasant but in the long run I think we reach a level of accommodation a lot sooner.
FWIW, I'm an atheist who married a woman from an immigrant muslim family although I've probably been in more mosques than she has.