“The decay of reason in politics is a product of two factors: on the one hand, there are classes and types of individuals to whom the world as it is offers no scope, but see no hope in Socialism because they are not wage earners; on the other hand, there are able and powerful men whose interests are opposed to those of the the community at large, and who, therefore, can best retain their influence by promoting various kinds of hysteria. Anti-Communism, fear of foreign armaments, and hatred of foreign competition, are the most important bogeys. I do not mean that no rational man could feel these sentiments; I mean that they are used in a way to preclude intelligent consideration of practical issues. The two things the world needs most are Socialism and peace, but both are contrary to the interests of the most powerful men of our time. It is not difficult to make the steps leading up to them appear contrary to the interests of large sections of the population, and the easiest way of doing this is to generate mass hysteria. The greater the danger of Socialism and peace the more Goverments will debauch the mental life of their subjects; and the greater the economic hardships of the present, the more willing the suferers will be to be seduced from intellectual sobriety in favour of some delusive will o’ the wisp.”

- Bertrand Russell, ‘The Ancestry of Facism’ (transcribed by measured-response)


Some of this smacks too much of conspiracy theories, but invoking mass hysteria is indeed a way of distracting and controlling the populace.