On 22 November 1963, Lee Harvey Oswald assassinated President John F. Kennedy in Dallas, Texas. A revolutionary zealot and a committed communist, Oswald’s journey to violent radicalization began when he was handed a “Save the Rosenbergs” pamphlet in New York City.
The first instance we have of Lee Harvey Oswald's politics is that he picked up a leaflet in New York City about the coming execution of the Rosenbergs. And as he reads this, it begins to show him that there's a way of finding himself by opposing the established order.
Edward Jay Epstein
What made the Rosenberg pamphlet memorable to him, surely, was that he saw himself in the “innocent victim” of a New York court. He held in his hand a message that said to him: Here are allies you can identify with. Here are people who feel as you do about the legal system.
The chain of events that ended in the murder of JFK began when a troubled, alienated teen-ager was ensnared by a fashionable conspiracy theory.
We usually don’t think of the JFK assassination in this way. Yet, it is undeniable that Oswald’s ideological awakening started with the Rosenberg pamphlet. He explicitly noted this event in explaining how he became a Marxist and defector to the Soviet Union.
It is also undeniable that to believe that the Rosenbergs were innocent one had to believe that high level government officials manufactured evidence, coerced perjury, and forged documents. In short, a massive conspiracy to frame two innocent people. Since we know they were far from innocent, what else should we call it but a “baseless conspiracy theory”?
It was fashionable, though, so it did not receive the disdainful debunking administered to theories accepted by less privileged people. Journalists, screenwriters, academics promoted it for decades. It took real bravery for Ronald Radosh and Joyce Milton to debunk it in The Rosenberg File
Even then the die-hard believers persisted. They never faced the vitriol and ridicule meted out to other conspiracy theorists. The SPLC did not label them dangerous, enablers of radicalization, or inciters of potential assassins.
For over half a century enormous efforts have been made to shift the blame from Oswald, the Castro-loving communist, to more politically expedient villains right-wing oil men, CIA, the military-industrial complex, the Mafia, right-wing hate vibes, etc., etc., etc..
A great deal of intelligence can be invested in ignorance when the need for illusion is deep.