I have a friend who’s a 9/11 Truther. Without getting into the specifics of the debate, such as it is, I’ve noticed, in discussing the topic with him over the years, a definite parallel between Truthers and the Intelligent Design crowd.
The ID’ers don’t believe that humans resulted from evolution because such a complex life form couldn’t possibly have come into existence without the help of an omniscient and omnipotent being.
Truthers, all supposed facts aside, don’t believe that 9/11 could have been the work of 19 hijackers because such a complex operation couldn’t possibly have been pulled off without the help of an omniscient and omnipotent organization (i.e., the US government and/or the Israelis).