As explained Clark is compelled to dispute controlled demolition and skunk the thread as otherwise he feels personally culpable for the crime as a real or honouree member of the tribe. I find it an entertaining study in itself grappling with this ancestral madness which confirms a prejudice.
I can understand why some find his posts at best tiresome sophistry that ruin a thread about 9/11, but you only need to view the collapse without blinkers to know it could only happen with the aid of explosives. So its a settled matter that many people avert their eyes from because they fear what they see.
In truth there is no need to debate Clark, just make comments and attach links to 9/11 sites (Craig’s other closed 9/11 thread is a wealth of information) and authors and let people do their own research. That said Clark is a clever clogs and does raise fair points on other subjects.