Stephen Sackur speaks to renowned academic Gilles Kepel, an expert on Islamist terrorism in France and beyond. His work is influential - it was cited by newly elected French president Emmanuel Macron during the recent campaign - and to some, controversial. In the wake of the terrible suicide bombing in Manchester, a familiar question is being asked again - is the West any closer to an effective counter terror strategy?

(Photo: Midlle East specialist and Professor at the Paris Institute of Political Studies (IEP) Gilles Kepel, 2012. Credit: Joel Saget/AFP/Getty Images)