The United States and France differ greatly in their responses to mass immigration. The U.S. adapts is own culture and that of the immigrants, most recently with Latinos. France wants the immigrants to do it all. As a result, the Muslim North Africans of France's first wave of mass immigration are not assimilating well. The author compares the two current cases and briefly discusses the policy implications: The U.S. seems on its best course, but France needs policy changes to at least keep the peace.