Jihadist terrorism is alive and kicking. And though we must continue to put terrorists on the back foot by targeting their leadership, we will never kill our way out of this phenomenon. In January 2013, after Bin Laden’s death but long before ISIS’s emergence, my counter-extremism organisation Quilliam declared (to choruses of raised eyebrows at the time), “It’s a full blown jihadist-insurgency, stupid.” And no insurgency is sustainable, or even possible, without a level of residual support for its core ideological aims among the core communities from which it draws its fighters.

Jihadism has well and truly taken root among an entire generation of angry young Muslims. This is particularly the case in Europe, where thousands have left to join ISIS. This insurgency is incredibly hard to tackle, because its recruits remain invisible in our very own societies, born and raised among us, fluent in our languages and culture, but full of venom for everything they have been raised into.

Though London is by now well overdue a similar attack, a question that could legitimately be asked is why does France seem to be bearing the brunt of such coordinated jihadist terror, up until now most potently symbolised by the Charlie Hebdo attacks. Unfortunately for France, though not unique to it, between 5 and 10 percent of its population is Muslim. Real, serious problems with economic and social integration prevail in this group, fuelling resentment on a scale that baffles most expert policy makers. Even if hundreds, out of millions, take this resentment to its deadly conclusion, France has a huge problem on its hands, as we saw on Friday. But so do we all.