This is probably the most comprehensive article about the background to this situation and reasoning as to why McAfee seems to be losing his mind: http://gizmodo.com/5960138/the-crazy-secret-journal-of-john-...
I think that North Americans sometimes don't realize that one of the reasons that the rest of the world is susceptible to urban legends and conspiracy theories is because in those countries, similar stories have been known to hold true. Nothing like a moon landing of course, but presidents and prime ministers have in fact been involved in murders, drug charges and fraud. In that context you're more amenable to think, "Yeah, this could have happened."
Does anyone have a link to the original source?