The issue of Europe certainly isn't going to be helped with a huge, and growing, muslim population.
That depends on whether the Muslims can be Europeanized before Europe is subjugated. I wouldn't give two hoots for French Muslims threatening the world. However, Islamic Frenchmen is a different issue.
Q: What did the French Suicide Bomber do after learning what he was recruited for?
A: Change his pants.
Shalom.