Who knows for sure. If not for their oil, we probably wouldn't even care much about Islamic countries if their people stayed home and didn't try to bring Islam with them, and we likely wouldn't pay them much attention if they kept their terrorists at home and away from us and others - particularly allies. Of course they do have oil - lots of it, so that tends to change things a bit; I suppose it's a matter of opinion as to whether that is considered involving ourselves in their affairs. Two big factors that influence buying oil from Islamic countries - OPEC, and Islamic countries were founding members - cartels are just a nice name for international price gougers. They also tend to get uppity and cut off oil when they don't like something going on in the world. The other is that Islamic countries go to war with each other and disrupt oil supply.
Overall, nations ruled by a religion can be difficult to live with, and I've noticed that one of the major sources of unrest around the globe has been rooted in religion. Religion is essentially a good thing; but like most good things when taken to extremes, it shows a very ugly side. It's always seemed ironic to fight in the name of a peaceful god or a religion. You might say religious zealotry is a killer. Personally I don't care much either way about Islam itself, but I am offended by their treatment of women as second class subjects and their inability to be self moderating (Ca va Charlie? Toujours mort). And, of course, there's that mostly peaceful bunch of raving lunatics in Iran who feel the need for nuclear weapons.