“He was highly important. He was the man on their media front line,” said Ahmed Rashid, a Pakistani author and expert on the Taliban and al Qaeda.

“Given the success of ISIS in media and social media, he would have been much needed, especially in communicating with English-speaking audiences and on web sites and so on,” he said, referring to Islamic State…

“He was the main man in charge of the al Qaeda narrative, so his death will have an impact on the propaganda machine,” said Amir Rana, author of a book on militant groups in Pakistan.

U.S. officials said Gadahn was killed five days after a U.S. drone strike in January targeting an al Qaeda compound in Pakistan inadvertently killed an American and an Italian who had been held hostage for years by the group.