Maybe it's the constant demonisation of their religion, by institutions like the media - 24/7/365
I'm not saying that Islam is completely *innocent* but I think a lot of the problems we have, could quite possibly be down to the bullish nature of how society treats followers of Islam, I don't think that means it's societies fault either, but I think creates an 'us and them' mentality (created by both sides) which is very hard to get away from once it's reached that point.
I think there's some truth to this, though I think it's less the media on our side and more the public in general. It's tribal and seems to just flow down the bloodlines. My ex was from a Muslim background and whilst she decided early on in her life not to pursue her families faith, the abuse she sometimes got whilst out in public was despicable. There was even an incident when we where out together and I got called a race traitor (I'm white British). We where followed for a good few minutes. Wasn;t like it was a rough area either, fairly aspiring middle class. She had friends that got it even worse. It just drives a knife between communities of people.
Not too say that there AREN'T despicable people out there actively recruiting for these groups, but... you know...