I think this would be a logical first step and would solve part of the problem. However, many of the troublemakers are native born citizens who will have to be confronted by all resources available to the government, including martial law and the military.
I know that many of the troublemakers are native-born citizens,and are in fact on their second or third generation as "French citizens.I am sure masses of Frenchmen in or out of government recognize THAT fact as one that makes their situation as a homogeneous culture even knottier and more intractable. The laws that need to be passed would have to apply EXCLUSIVELY to them as individuals: I am sure there are some tricky legalisms that can be employed within new Law of the Land legislation to help the deportation process. In times of crisis, nations do temporarily up-end some existing laws.