1. Islamic Ideology
Islamic extremists are a persistant and reoccurring problem, but by themselves they're not very popular. They have two things really going for them now that makes them a potent threat: widespread discontent, and vast financial resources. Without those two factors, they'd be a tiny fraction of their current threat.
2. State Nationalism
Beyond idenifying with a state, ethnic group, or tribe, the biggest cause of discontent in the region is the fact that they have appallingly bad government. In most cases, the ones holding the oil developed a stranglehold on the country and wound up running things, usually throwing cash at people to buy them off, including radical Imams. It's hard to overstate how deeply this discontent runs, or why radical Islam would be seen as an attractive alternative to repression, but that's how it is.
3. Trade(oil)
I think that oil would rank #1 or #2 with both them and us. Honestly, we'd spend no more focus on the Middle East than we do Tanzania if they had no oil, and everyone knows it. The Middle Easterners far more than us realise that. They openly resent our support of local dictatorships as a way to keep them in a perpetual banana republic stage of development, simply to keep the oil flowing and our economies running strong. Our policy appears to them to be "Do what's good for business, and the locals be damned."
To a great extent, they're right. That double standard makes our cries for 'freedom' and 'democracy' sound hollow and calculated.
They'd like to believe us and to believe in what we say we stand for, but they don't see our actions backing that up. Radical Islam, for whatever bad can be said about it, does believe what it says and acts accordingly, no matter how cuckoo it is.
Schuerer always demonstrates why his colleagues ignored him. He does claim, however, that they delivered bin Laden to Clinton 10X with sighters on the ground and eash time Clinton passed.