On September 11, 2001, I was enjoying the tail end of my summer holiday with family in Connecticut. Over the past year, I had been studying Osama bin Laden’s enigmatic fatwas as a graduate student at Oxford. At the time, al-Qaeda was not well known, so I was surprised to find that in the climate of paralyzing fear after the attacks, everyone around me professed to know exactly why this group had struck the United States.