Quite the article here.
You must read the whole thing.
"What these cases show is that it is not Islam that makes young converts violent; it is the violence within them that causes them to convert to Islam. The religion, in its most bloodthirsty form, supplies all their psychological needs and channels their anger into a supposedly higher purpose. It gives them moral license to act upon their rage; for, like many in our society, they do not realize that anger is not self-justifying, that one is not necessarily right because one is angry, and that in any case even justified anger does not entail a license to act violently."
"The hacking to death of Lee Rigby on a street in Woolwich tells us as much about the society that we have created, or allowed to develop, as it does about radical Islam preached by fat, middle-aged clerics."