" The Prophet Muhammad, peace be upon him, taught us there were Five Pillars of Islam. We believe there is a sixth. Jihad is not a choice. It is an obligation. The al-Saud understand this. Once again, they are willing to look the other way, provided the brothers don’t make trouble inside the Kingdom. That was Bin Laden’s biggest "

― Daniel Silva , Portrait of a Spy (Gabriel Allon, #11)