Prime Minister Manuel Valls says France is now at war, among other things, with what he calls radical Islam. And the French interior minister says Paris will increase security co-operation with other countries to fight what he calls terrorism.
But is that the answer? And who is fuelling religious radicalisation in France and elsewhere in Europe?
Alain Gresh - Journalist for Le Monde Diplomatique and Specialist on the Middle East.
Khaled Diab - Journalist, Writer and Blogger.
Renaud Girard - Chief Foreign Correspondent for Le Figaro.