The Empire Needs New Clothes by Thom Hartmann. Summation: It's about oil, but not in the way you might think.
Note to conservatives: read it with an open mind.
Note to liberals: don't read into it vindication for demonizing a particular president.
Note to libertarians: No notes actually, I just didn't want ya'll to feel left out. You've probably known about this theory for a while anyway.