American politics has often been an arena for angry minds. In recent years we have seen angry minds at work mainly among extreme right-wingers, who have now demonstrated in the Goldwater movement how much political leverage can be got out of the animosities and passions of a small minority. But behind this I believe there is a style of mind that is far from new and that is not necessarily right-wind. I call it the paranoid style simply because no other word adequately evokes the sense of heated exaggeration, suspiciousness, and conspiratorial fantasy that I have in mind. In using the expression “paranoid style” I am not speaking in a clinical sense, but borrowing a clinical term for other purposes. I have neither the competence nor the desire to classify any figures of the past or present as certifiable lunatics., In fact, the idea of the paranoid style as a force in politics would have little contemporary relevance or historical value if it were applied only to men with profoundly disturbed minds. It is the use of paranoid modes of expression by more or less normal people that makes the phenomenon significant.
Of course this term is pejorative, and it is meant to be; the paranoid style has a greater affinity for bad causes than good. But nothing really prevents a sound program or demand from being advocated in the paranoid style. Style has more to do with the way in which ideas are believed than with the truth or falsity of their content. I am interested here in getting at our political psychology through our political rhetoric. The paranoid style is an old and recurrent phenomenon in our public life which has been frequently linked with movements of suspicious discontent.
[from "The Paranoid Style in American Politics"
By Richard Hofstadter
Harper’s Magazine, November 1964, pp. 77-86.]