Every account of September 11 eventually arrives at the same unanswered question: what did the man who ordered it actually think he would achieve? The instinct is to treat it as an act of pure hatred, needing no further explanation, but bin Laden himself refused that framing. He explained his reasoning at length and more than once, in a 1996 declaration of war, a 1998 fatwa co-signed with several other jihadist leaders, and a lengthy 2002 letter addressed directly to the American public.