prosecutors say bryant viÑas may have been the most valuable witness ever in the war on al qaeda. essed prosecutors and the judge in his case so much that they prepared to shield him from the prospect of al qaeda's revenge by putting him in the federal witness protection program. all was prepared-- until bryant viÑas says he was double-crossed. you can assume that al qaeda wants to kill you. >> bryant viñas: yes. >> pelley: right now, today? >> viñas: yes. >> pelley: why be on television? >> viñas: to let people know what went wrong. >> pelley: life went wrong for bryant viÑas at an early age. he was a troubled teenager. his mother kicked him out. viÑas was searching for purpose and converted to islam. later, he was seduced by the online fanaticism of al qaeda recruiter anwar al-awlaki. >> anwar al-awlaki: we are fighting for a noble cause. we are fighting for god. >> pelley: al-awlaki was an american killed back in 2011 by a u.s. drone. >> viñas: a lot of his sermons were captivating. very mesmerizing, i guess you could say. he was talking about the injustices in the world, oppres

>> there's no question bryant viÑas betrayed america by joining al qaeda.at you'll have to decide for yourself is whether heas