The Muslim influx was a result of colonial France. Britain has a sizeable Muslim population which is doing relatively well. The problem was discrimation and non-integration. Muslims (of North Africa) are unfortunately INA similar position as blacks in the USA.

The only common factor being their economic status.

But the Arab French have integrated culturally and are highly successful artists, athletes, businessmen, etc. Its only a matter of time before they deliver on the promise of immigration.

P.S. I'm a Muslim of South Asian origin born in Saudi Arabia.