Perhaps what the author says about Osama's mental state is true. But to try to pin all of this on one man is dangerous and stupid. Their are 1.3 billion of the Islamic believers in the world and a larger number than we think read the Koran the same way he does.
I personally don't care if a person worships turnip greens, that's their right. But any belief system that spreads by the use of terror and force, celebrates the use of it's children for cannon fodder, teaches then to hate others to the point that they will commit suicide to kill non-members of that faith and treats their women like cattle, is evil personified and needs to be condemed.
Look around the world and see what they have done and are doing. Maybe people like him are a minority of that system, but a minority of 1.3 billion can be a hell of a lot of fanatics.
Like a number of losers in Western countries, these would-be fanatics need something to keep them going. Your own country and personal life are both extremely substandard, so why not latch on to something you can get excited about and release all your pent-up frustrations at your nothing existence. Hate is just as big of a motivational factor as love. These people have plenty of hate and they probably hate themselves most of all. Many are easily led by pied pipers of murder like Bin Laden. But when and if push comes to shove, doubtless many of the fervent will shrink back into their previous states of smoldering inaction. That is if they are not dead from the actions of the real but much-smaller percentage-wise hardcore fanatics who will get thousands if not millions killed from their rebellion against the West and civilization.