The obvious and logical solution of course is to round up all the muslims, put them on ships, and tell them to never set foot on French soil ever again. And it goes without saying that Islam would be forever banned in France. That's the logical solution to prevent a nightmare worse than Orwell's Oceania. Naturally the French won't do that. They will try to placate the Islamic barbarians and accomodate them. I shudder to think what France will be like fifty years from now.
If this is to work, make sure it is a certain French aircraft carrier. They'll either starve to death or drown before they get half way to anywhere.
Either that, put them on Canadian submarines.