Conspiracy theories are beliefs that covert and deceptive organizations or groups are responsible for important world events, and that these people are hiding their own involvement, acting from behind the scenes and spreading misinformation. Usually, the term is used pejoratively, to denote irrational, paranoid and empirically unsupported beliefs that purport to describe world events through all-powerful unseen agents, and attribute almost-magical or supernatural powers to the supposed conspirators. These beliefs often fall foul of Occam's razor, are unfalsifiable, often illogical, based on political presuppositions (often of an extreme kind: racist or anti-semitic). They also often tend towards being amorphous and all-encompassing, explaining absolutely everything. Those within political movements (of all stripes) which conspiracy theorists ally themselves with are often keen to distance themselves from conspiracism.
Conspiracy theories are often dominated by secret societies and groups: the Jews, international bankers, Masons, the supposed New World Order, fraternal groups like Yale University's Skull and Bones society, the Roman Catholic Church (or groups within the Church like the Jesuits or Opus Dei), the Knights of the Templars, the Bilderberger Group, the Council on Foreign Relations, the Rockefeller Foundation, leaders of the nations in the European Union, Satanists, the medical, psychiatric or legal professions, among many others. These groups are said to use power in all forms, dominating all institutions in society: schools and universities, the government, churches and religious institutions, the media, business and the military. These conspirers are said to operate in ruthless ways: playing ideologies and countries off one another, masking their true intent behind multiple layers of facade, and hiding their secrets both far out-of-sight in their eerie catacombs and secret crypts, and in plain sight in their public-facing symbols and the naïve dismissal of ordinary people.
Scholarly reaction and research
The American historian Richard Hofstadter was one of the earliest to have discussed conspiracy theory as a specifically American phenomenon. In The Paranoid Style in American Politics, Hofstadter describes a "sense of heated exaggeration, suspiciousness, and conspiratorial fantasy" of otherwise ordinary people that can be traced from fears about the Illuminati and the Freemasons at the turn of the nineteenth century to fears of the Jesuits and Catholics in general, to income tax denialism and finally to McCarthyism. This enemy of freedom operates ahistorically and callously:
Unlike the rest of us, the enemy is not caught in the toils of the vast mechanism of history, himself a victim of his past, his desires, his limitations. He wills, indeed he manufactures, the mechanism of history, or tries to deflect the normal course of history in an evil way. He makes crises, starts runs on banks, causes depressions, manufactures disasters, and then enjoys and profits from the misery he has produced. The paranoid’s interpretation of history is distinctly personal: decisive events are not taken as part of the stream of history, but as the consequences of someone's will.
Many journalists, academics and commentators have made reference to Hofstadter's essay and conception of the "paranoid style" to describe the Tea Party Movement in American politics, as well as public figures who have identified with it, such as Glenn Beck and Sarah Palin.
By no means is this uniquely an American phenomenon. Adolf Hitler consistently put the Jews at the center of Germany's problem, and based his demagoguery on the Jews, and what he termed their Communist ideas. Joseph Stalin based the Great Terror on various groups conspiring against him and the Soviet Union. Stalin did have enemies, but not as organized millions.
Peter Knight, a British academic, describes the common image of a conspiracy theorist as "an obsessive, petty-minded right-wing paranoid nut, a proponent of extremist politics with a dangerous tendency to single out the usual suspects as scapegoats". Knight argues that conspiracy theories have gone from being the preserve of "cranks" to being an undercurrent of popular culture that matches the politics of contemporary America. Knight points to the rhetoric used by feminist writers like Betty Friedan and Naomi Wolf, and in black culture (accusations that the availability of drugs and guns in black neighborhoods are a plot by powerful whites, that AIDS is an intentionally created plague that targets blacks) - as well as the popularity of conspiracy-based shows like The X-Files - as showing that the rhetorical strategies and ideas underlying conspiracy theories have seeped into mainstream consciousness.
In 1994, Ted Goertzel published research in the journal Political Psychology where he surveyed 348 New Jersey residents and found that most believe in at least ten conspiracy theories. He also stated that belief in conspiracy theory correlates with anomia, lack of interpersonal trust and insecurity about employment. The research also looked at a variety of other factors and found that blacks and Hispanics were more likely to believe in conspiracy theories, and younger people were slightly more likely to believe in conspiracy theories. Other factors including gender, education level and occupation had little correlation of any significance.
While the line sometimes seems hard to draw, there is a good deal of acknowledged entertainment based on conspiracy. The 1967 movie, "The President's Analyst", features a sinister organization called TPC, eventually identified as The Phone Company. As mentioned, the X-Files were immensely popular.
Conspiracies in reality
Conspiracy may be added to other criminal charges, when the criminal act requires the collaboration of multiple individuals. This applies both in national and international jurisdiction; many war crimes tribunals have issued indictments for "conspiracy against peace" or "conspiracy against humanity". Insider trading in financial markets requires conspiratorial exchange of non-public information.
Intelligence and other clandestine services, of course, must conspire as part of their daily operations. The fictional title "infinity of mirrors" is a popular description for the world of counterintelligence,  and the saying "you don't have to be paranoid to work here, but it helps," is common black humor in the real secret world. James Jesus Angleton, head of the Central Intelligence Agency counterintelligence staff, eventually was forced into retirement when his belief in complex Soviet conspiracies outweighed his usefulness and his patrons.
While tyrants such as Joseph Stalin and Adolf Hitler would launch massive purges against those who might or might not be conspiring against them, there unquestionably were real conspiracies aimed at them. Even paranoids have enemies.
- Richard Hofstadter, The Paranoid Style in American Politics, Harper's Magazine, November 1964.
- Richard Bernstein, An Old Essay Used to Explain a New Movement, The New York Times, March 10, 2010
- Peter Knight, Conspiracy Culture: From Kennedy to the X-Files, p. 3
- Goertzel, T. (1994), "Belief in conspiracy theories", Political Psychology: 731–742
- Richard Condon (1964). An Infinity of Mirrors. Random House.