Since the early days of French history, there as been a lot of immigration. Early on, the French used immigrants to help to fund and participate in it's many war efforts. Most of these immigrants came from Europe of Africa. These two parties aren't exactly the same, as you're well aware. This, of course, created some social tension in France that has continued to cause problems in France.

Ever since there was a large influx of African immigrants (many muslims) , France has taken a position of favoritism to help preserve it's culture. This means giving better jobs and benefits to European immigrants, and not their African counter parts. More recently, there have been social clashes between the French and their Muslim guests regarding head scarfs for women. As they had become a distraction in schools, the French decided to forbid all public signs of religion schools.

This obviously created problems for many people, and it will be awhile before we see this issue resolved in France. The question is, will this large influx in people who don't fit the French 'norm' simply cause a melting pot effect, where both cultures can live together or will it create more of a salad bowl affect, where both cultures are present but at ends with each other.