Two years ago, it was banned outright during a crackdown on extremism after the killing of two leftist political leaders. But a government still establishing its authority after years of dictatorship has struggled to stamp it out altogether, not least because of the country's porous border with Libya, where Isil militants now have a hold. And with post-Arab Spring Tunisia still suffering from painfully high unemployment, the same sense of despair that drove Mohamed Bouazazi to self-immolation is motivating plenty of other young Tunisian men to give up their lives for jihad.