Perhaps a difference between "immigrant countries" and "non-immigrant countries" is that they DO adapt to the immigrants. Canada is a lot different now, with her many recent immigrants from the Far East, then she was 50 years ago. The U.S. has adopted characteristics from each new tide of immigration and is completely different now from how it was in, say, 1800 (when it was mostly British), 1850 (many new Germans), 1900 (Irish and Italians) and 1950 (European Jews).

If France is to successfully integrate 20% of a population that is Black, African, and Islamic, it will become a more Black, African, and Islamic country.