from the Rolling Stones Interview:
http://www.rollingstone.com/music/features/yusuf-islams-golden-years-cat-stevens-on-islam-and-his-return-to-music-20150113

Over the years, Yusuf's children tried in vain to get him to begin playing guitar again. Then, a few months after 9/11, Yusuf found himself holding an acoustic guitar his son had brought home. It was late at night, and his family was asleep. "I just thought, 'Let's have a go and try,' " he says. "I looked for F, and I found it. I don't remember what songs I played, but when it was done I began crying."

Yusuf was conflicted about playing again, but the war in Afghanistan was raging and another conflict was looming in Iraq.Yusuf says that the world needed to see at least one nonviolent Muslim on TV. "There was so much antagonism in the world," he says. "Many Muslims have come up to me, shook my hand and said, 'Thank you! Thank you.' I'm representing the way they want to be seen.

So much of the middle ground gets forgotten in the extremities we witness around the world."

From:
https://www.theguardian.com/music/2006/nov/11/folk.popandrock

I think we've got to push the premise that culture is something to be shared by everybody. It's not a divisive issue. Whenever anything is good, a lot of people flock to it and want it, and that's why I'm singing songs again."