In Jomini's book, "The Art of War" he addresses this in the section in article VII of his book, titled "War of Opinion."

Jomini thinks along the line of Bob's World, when he states ,

religion is the pretext to obtain political power, and the war is not really one of the dogmas. The successors of Mohammed cared more to extend their empire than to preach the Koran,
He then accused the crusaders of thinking more of expanding trade than spreading Christianity.

Final quote

The dogma sometimes is not only a pretext, but is a powerful ally; for it excites the ardor of the people, and also creates a party.
Regardless, we have a security problem on our hands that is expanding. It is unlikely we will be able to address the root political, social, and economic causes of which I'm sure there are many, so our focus IMO is reducing the threat through military action in ways that mitigate further agitating the underlying phenomena that motivates this behavior. No one said it would be easy, but ignoring the problem because we can't address root causes in my view is a dangerous cop out.