2. The US Government was behind it all
Well, it was inevitable for conspiracy theorists to come up with the idea that the United States government was behind the attacks and that Al Qaeda was just taking advantage of the entire situation and putting its signature on the attack because it suited their needs. Why would the US government do such a thing? Because it wanted to intervene in the middle East and it was looking for a reason to stick its nose in the region. However, on top of all the evidence proving that the terrorists were behind the incidents, there’s also the history lesson these people seemed to have skipped.
The governments that have ruled the United States in the past several hundred years haven’t exactly been shy to take what they wanted and to intervene where it suited their needs, without offering much of an explanation. Therefore, if they wanted to intervene in territories where the terrorist group had its headquarters they’d have found a better excuse for it, rather than killing thousands of its own people for it.