In her book The Origins of Totalitarianism, Hannah Arendt says that that the Soviet and Nazi totalitarian systems rested on mass support:
No doubt, the fact that totalitarian government, its open criminality notwithstanding, rests on mass support is very disquieting. It is therefore hardly surprising that scholars as well as statesmen often refuse to recognize it, the former by believing in the magic of propaganda and brainwashing, the latter by simply denying it…A recent publication of secret reports on German public opinion during the war (from 1939 to 1944), issued by the Security Service of the SS, is very revealing in this respect. It shows, first, that the population was remarkably well informed about all so-called secrets – massacres of Jews in Poland, preparation of the attack on Russia, etc. – and second, the “extent to which the the victims of propaganda had remained able to form independent opinions.” However, the point of the matter is that this did not in the least weaken the general support of the Hitler regime. It is quite obvious that mass support for totalitarianism comes neither from ignorance nor from brainwashing.