Nearly sixty years have passed since the assassination of President John F. Kennedy in Dallas on November 22, 1963. Nearly sixty years have passed, too, since Richard Hofstadter spoke at Oxford University on November 21, 1963, lecturing that “American political life . . . has served again and again as an arena for uncommonly angry minds.” Behind the emergent radical right, he continued,

there is a style of mind, not always right-wing in its affiliations, that has a long and varied history. I call it the paranoid style simply because no other word adequately evokes the qualities of heated exaggeration, suspiciousness, and conspiratorial fantasy that I have in mind.

The synchronicity of the two events is as appropriate as it is uncanny. Kennedy’s assassination came to represent, according to the historian Peter Knight, a “symbolic watershed” — a point after which notions of straightforward causality faltered and conspiratorial narratives flourished. And Hofstadter’s speech, which was adapted into a 1964 essay for Harper’s Magazine, “The Paranoid Style in American Politics” (and later a book of the same title), has formed the bedrock for the mainstream understanding of conspiracy theories.