Hannah Arendt again, from Origins of Totalitarianism:

Before they seize power and establish a world according to their doctrines, totalitarian movements conjure up a lying world of consistency which is more adequate to the needs of the human mind than reality itself; in which, through sheer imagination, uprooted masses can feel at home and are spared the never-ending shocks which real life and real experiences deal to human beings and their expectations. The force possessed by totalitarian propaganda — before the movements have the power to drop iron curtains to prevent anyone’s disturbing, by the slightest reality, the gruesome quiet of an entirely imaginary world — lies in its ability to shut the masses off from the real world. The only signs which the real world still offers to the understanding of the unintegrated and disintegrating masses — whom every new stroke of ill luck makes more gullible — are, so to speak, its lacunae, the questions it does not care to discuss publicly, or the rumors it does not dare to contradict because they hit, although in an exaggerated and deformed way, some sore spot.

…

The most efficient fiction of Nazi propaganda was the story of a Jewish world conspiracy. Concentration on antisemitic propaganda had been a common device of demagogues ever since the end of the nineteenth century, and was widespread in the Germany and Austria of the twenties. The more consistently a discussion of the Jewish question was avoided by all parties and organs of public opinion, the more convinced the mob became that Jews were the true representatives of the powers that be, and that the Jewish issue was the symbol for the hypocrisy and dishonesty of the whole system.

The actual content of postwar antisemitic propaganda was neither a monopoly of the Nazis nor particularly new and original. Lies about a Jewish world conspiracy had been current since the Dreyfus Affair and based themselves on the existing international interrelationship and interdependence of a Jewish people dispersed all over the world. Exaggerated notions of Jewish world power are even older; they can be traced back to the end of the eighteenth century, when the intimate connection between Jewish business and the nation-states had become visible. The representation of the Jew as the incarnation of evil is usually blamed on remnants and superstitious memories from the Middle Ages, but is actually closely connected with the more recent ambiguous role which Jews played in European society since their emancipation. One thing was undeniable: in the postwar period Jews had become more prominent than ever before.