Celebrimbor over at Quoth The Raven has an excellent post. He says

we are at war against the political ideology of islamisim, and YouTube is used to recruit fighters to bring the glories of sharia to the west. Would we have allowed the fascists to recruit fighters to bring the glories of nazisim to our shores? No we wouldn’t. Further, an American company that facilitated the radicalization of German youth would likely find themselves in deep trouble.

Check out his post on recommendations for what to do about it. And then JUST DO IT!!