Well, they are definitely jealous, because they are part of an anti-intellectual, anti-individual death cult, and yet somehow they are just too dumb to understand why their societies do not do as well as ours... Er, Ali, maybe it's something about that death cult?
Still, I think the appeal of Islam to people such as the Western converts who all immediately start trying to kill the rest of us is that, like any cult, it preys on people who don't have very clear religious beliefs of their own or see the religion practiced by those around them as tepid and ineffectual. The "hollowing out" of Christianity by its replacement with the social ideals of the Democrat party in most mainstream churches has definitely driven away millions of people who would have been believers and made it tepid and ineffectual.
Well, it goes without saying that people who are vulnerable to cults are empty people, looking for something to fill a void withing themselves. Unfortunately, most Muslims are born into it, and the mind control begins at birth. Such psychological damage is almost impossible to undo through rational thought and education. It doesn't really leave us much of a choice when dealing with those who believe that their only value in this world is to kill us.
In part, you can thank the Megachurch movement for that.