Here's a good article explaining the situation in Europe:
Along Came Sharia-Islam and European secularism clash.
Here's the conclusion:
The European Left's strong support for Muslim immigrants has traditionally been twofold: first, Muslims are a religious and ethnic minority in Europe and therefore advance the Left's multicultural agenda. Secondly, as evidenced by their joint participation in the antiwar protests of the past two years, Europe's Left shares with many Muslim immigrants a resentment of the U.S., Israel and capitalism. But virtually all other aspects of the two groups' belief systems are at odds: gay rights, women's rights, abortion rights, multiculturalism, separation of church and state, interfaith dialogue and opposition to the death penalty, all perennial Leftist causes, are opposed by an overwhelming number of Europe's Muslim immigrants, sometimes brutally so. As its ever-growing Muslim population continues to alter the Old Continent's social fabric, the European Left seems to be coming to the realization that the "enemy of my enemy is my friend" adage to which it has traditionally ascribed its support of mass Muslim immigration no longer applies. For many of Europe's Muslims, the most pressing "enemy" is not the U.S., Israel or capitalism, but the liberal, secularized way of life practiced by their "infidel" hosts.