Adam Yahiye Gadahn ( , '' Ādam Yaḥyā Ghadan '' ; September 1 , 1978 -- January 19 , 2015 ) was an American senior operative , cultural interpreter , spokesman and media advisor for the Islamist group al-Qaeda .
, '' Ādam Yaḥyā Ghadan '' ; September 1 , 1978 -- January 19 , 2015 ) was an American senior operative , cultural interpreter , spokesman and media advisor for the Islamist group al-Qaeda .