LATEST WHY THEY HATE US: It's the chemistry, stupid. Lead poisoning is apparently an ingrained part of Middle East culture:

"Does lead poisoning explain Osama bin Laden's madness?
Dr. Simanonok writes, "When I managed the blood lab at a northern California clinic for the poor, Pakistani children were often found to be contaminated with lead from the black makeup called 'kohl' that their mothers applied around their eyes. Middle Eastern mothers use it on their boys just as much as their girls.
"Lead poisoning is especially bad for children because it can reduce their IQs dramatically and cause developmental problems. In both children and adults, problems associated with lead poisoning increase with blood levels, from behavioral and learning disorders to various physical ailments including high blood pressure and kidney problems, even at moderate levels. At very high levels, lead can cause convulsions, paralysis, coma or death.
"Besides the fact that many Arab cultures have a history of prolonged lead exposure through kohl (with nothing like our EPA or FDA to limit any of it), lead poisoning should especially be considered a possible factor in recent events because many Arab fighters, including some of the Taliban, traditionally use kohl around their eyes.
"Some pictures of Osama bin Laden certainly suggest he might be wearing kohl, and it is known that he suffers from kidney problems. Lead poisoning could explain bin Laden's kidney problems and could only contribute to the madness of suicide bombers under the influence of malignant religious views."

I hope the doctor isn't conflating Pakistanis with Arabs, though. (I wonder if Matthew Edgar agrees this is a good reason for the FDA's existence.) Unisci provides this article on the further mental-incapacitation effects of good old Pb.