Perhaps Aaronovitch Voodoo Histories: The Role of the Conspiracy Theory in Shaping Modern History could have started his review a little earlier to better understand the origin of why conspiracy theories are such an important part of our collective consciousness. The Bible and the Koran would be a good place to start. While many of those in power in a society are still able to declare their belief in the murder and miraculous resurrection of a holyman to save us all from eternal damnation and expect to be taken seriously, is it any wonder that more recent conspiracies are given credence. And surely, if nothing else, the book of Revelation is a grand conspiracy fantasy. You can hear him talk about it here.