This is absolutely true. People will pervert anything and make it work to their advantage, including religion, or perhaps more appropriately, especially religion.
I remember reading a quote once that pretty much sums stuff like this up. "In any given group of people you will have a few who lead, some who follow, and some who just don't care." In this case you have one idiot leading, and a whole bunch of idiots following him. 9/11 wasn't the result of religious conviction or worship, it was a group of idiots perverting religion to make what they did seem justified to themselves. Anyone who is willing to kill a whole bunch of folks they don't even know, and who have never done anything to them personally, is nuts, just plain and simple fucked in the head. That's not something that's unique to Muslim extremists, you find those folks all over the place.
I'm not sure what religious affiliation Iggy is, or perhaps he's not at all, but I'm a Christian and I believe more people have been killed under the auspices of spreading and defending the Christian religion that by any other religion. Does that make me a murderer, no clearly it does not. So the concept of holding an entire religion responsible for the actions of one faction is completely ludicrous. I wouldn't want anyone to do that to me, I'm sure not gonna do that to someone else. Do unto others as you would have them do unto you is actually good advice.