The recent rioting in Paris suburbs and elsewhere in Europe should not have surprised anyone. Europe's Muslim communities are powder kegs, brimming with an alienation born of both an assiduously inculcated antagonism toward infidel society and an infidel society whose integration policies - which should actually be called segregation policies - have perversely encouraged this ire.

I first noticed the problem when I lived in Amsterdam in 1999. A visitor to that city might imagine that not one Muslim lived there. But to venture just a few blocks beyond the tourist-crowded streets was to learn otherwise. In my neighborhood, the sidewalks were crowded with hijab-clad women pushing baby carriages. There were as many signs in Arabic as in Dutch. Outside the "neighborhood center" waved a large Turkish flag.

Such districts, I learned, could be found across Europe. Muslims were a huge, rapidly growing - and highly segregated - minority. In city after city, downtown areas were almost 100 percent European, the outskirts increasingly Muslim...

...This refusal--the official denial that ethnicity can have any legitimate place in public life--reflects the republican ideology that lies behind France's model of immigration. Republicanism resolutely opposes any show of loyalty to an entity other than the nation itself, whether an ethnic group, a geographical area (such as a French province), or a religion. As long ago as 1789, a legislator memorably articulated the key idea in regard to the group that, until very recently, was seen as most different from the French norm, and around which discussions of ethnic difference tended to crystallize: "Everything must be refused to the Jews as a Nation ... and everything granted to the Jews as individuals." In recent years, the most ferocious debates over French identity have not concerned immigrant groups, per se, but Islam, and particularly the wearing of headscarves by Muslim girls in the public schools, which the French state has banned. To dedicated republicans, the headscarf is precisely the sort of badge of identity that threatens to trump one's identity as a citizen and endanger civic unity...

...France always thought it had one last resort, one ready strategy for fending off the rage of its Arab street: beyond avoidance lay appeasement. No country in the West has done more to cultivate world Arab opinion, to appease Arab terrorists, to ostentatiously oppose American Middle East policy (Iraq above all), to champion the signal Arab cause of Palestine. It was no accident that Yasser Arafat chose Paris as his place to die--Paris, after Jerusalem, his second holiest city.

Paris burns anyway. As the French seem to learn every 70 years, appeasement does not work. It merely whets the appetite. And the angry alien young were already hungry.