That is what the conspiracy is. In senses, it is completely believable in some areas. Think about it this way, says you are a bank manager and out of the people who applied, your brother was one of them. Would you show favour to your brother and employ him? Typically, even though we might not admit it, the general answer is yes.
Now widen this, to family and friends. Would you do the same? Typical answer is yes.
What about your community, let's say you are a strong church goer and some one you knew there which you got along well with, you generally show favouritism and they get that job.
With secret societies such as Freemasons, Skull and Bones, etc, this is what happens, they are members of these communities and these people look after eachother. You rub some one elses back, they rub yours. This way, let's say members got into big serious positions, they get other members in other ones and soon enough, a society could gain a foothold in that area and could be argued as such, this happens with politicians. If we were a true meritocracy, what are the chances of a grandfather, father and son getting into positions of power like they did, even with the latter two being US presidents? Or the case of even two seemingly random people (Bush and Kerry), even in different parties end up belonging to the same secret society. The so-called Old Boys clique which is present in Westiminister in British Politics (The Eden boys).
It is these processes how things like this happen, if you say it small time, such as a butcher showing favour to a friends son, you wouldn't bat an eyelid, but what about a US president appointing some one as head of the federal reserve (or a powerful position similar to that).
The whole idea is that a cabal, full of these different groups are seeking World Domination, in a sense, a league of evil villains and instead of superman versus them one by one, unable to sololy do it themselves, the super villains work together and therefore defeat superman and actually win. It is this self-interest which sprout all sorts of secret societies, meetings and other things, such as Bohemian Grove and Bildenburg.
The whole idea of secret meetings bring panic and disturb people. Imagine world leaders in various areas all having a party together, rubbing eachother backs, doing seedy deals, wanting to further agendas which to men and women on the street are strict no's. lack of transparency and accountability.
It is this primal fear which gives wake to the terrible idea of the grand conspiracy, the conspiracy of the New World Order of total domination over the planet. Secret Organistations dating through hundreds of years, considerably changing our very history through their political manoeuvring. From the fall of governments, to the rise of new ones, the self-interest, creating divides, trying to conquer us all.
The question really is - Are these groups really working together as a cabal for the grand conspiracy or not? The question of existence is a non-issue, they really do exist, it is whether or not, as a matter of faith, they are the embodiment of our worse fears.
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