Well, to be honest about it, there have been schools in Pakistan and Afghanistan that have been producing brainwashed Jihadists for a long time. Madrasas create a jihadist and they will find some excuse to use what he's learned. It isn't like Osama or anybody else is going to declare an end to a jihad and then all of the fighters go home to become ordinary peaceful citizens again. They're going to find themselves another jihad.