Militant Islamist fighters waving flags, travel in vehicles as they take part in a military parade along the streets of Syria's northern Raqqa province June 30, 2014. REUTERS/Stringer
Islamic State militants lead what are said to be Ethiopian Christians along a beach in Wilayat Barqa, in this still from an undated video, released April 19, 2015. REUTERS/Social Media Website via Reuters TV
Members of the Yazidi sect, among the 200 elderly and infirm released by Islamic State militants, on the outskirts of Kirkuk, April 8, 2015. REUTERS/Ako Rasheed
The Mosque of Mohammed Ali in the Citadel (top), the Sultan Hasan Mosque and the Al-Rifa'i Mosque (bottom right) in Cairo, May 20, 2008, REUTERS/Nasser Nuri
How do you reconcile the traditions of many Muslim immigrants with the freedoms and values of 21st century Western Europe?