"All within the party, nothing outside the party". The CIA, makes many of the major decisions for the u.s (the sort any people believe are made by the show-government in congress and the senate). They are the new hybrid model of a closed system - not easily subverted, but open to new information. They dont burn books like their predecessors in the Soviet union. This is not the same as censoring information that would be available to the public. The idea is to make sure they dont blindside *themselves* by preventing the elimination of *internal* information. The hybrid model means that they use both official and unofficial channels for growing the employee and affiliate base of the regime, or org, or inner party. So they might leave this material up for "public consumption" with the purpose of plausible deniability, or even to boost its legitimacy (perhaps being written by the regime itself). In order to cultivate a subset of the population as affiliates for a variety of uses from killers (see Jack ruby for details), to political operatives who form the puppet political segment i.e the outer party. There is always a need for warm bodies for the machine, and it is important that a sufficient number of them *do* have some element of *real* education about how the regime works, so that they can be both effective and the regime can remain functional. (For some definition of "functional") The first example in history of this phenomenon was machiavelli's *The Prince*. The reaction by the political sphere was meant to say "this is forbidden" but also "this is true." It's a filter to weed out the stupid, the weak, and the gullible. And anyone that reads it and a history of other works, is taking the risk of "volunteering" to be rope-a-doped later on into any number of roles the regime may need them for. Or did you think everyone in the outer party was there voluntarily? Some of them were forced from the moment they attended yale. Or read the wrong books. Try telling the regime no.