You can't get people to believe a truth whose jobs and careers depend on disbelief either. When even their lives may depend on at least pretending to disbelieve, they will do so.

That job was a well-planned demolition...with or without the aid of a handful of Muslims with boxcutters. It has enabled the unprovoked invasions of two entire foreign countries, the death of a great many innocent people, and it may yet enable far worse than that...if yet another attack is launched on Iran.