Why most Americans doubt the official version

Immediately after Kennedy’s assassination, given Oswald’s history, the USSR considered him a major danger to stability between the two countries, which had improved during Kennedy’s administration.

One source told US intelligence officials: “Soviet officials were fearful that without leadership, some irresponsible general in the United States might launch a missile at the Soviet Union.”

They also apparently believed he was part of a wider plot to kill the president, launched by farright groups in the US.

According to the documents: “Officials of the Communist Party of the Soviet Union believed there was some well-organised conspiracy on the part of the ‘ultra-right’ of the United States to effect a ‘coup’. They seemed convinced that the assassination was not the deed of one man, but that it arose out of a carefully planned campaign in which several people played a part.”

The document adds: “They felt that those elements interested in utilising the assassination and playing on anti-Communist sentiments in the United States would then utilise this act to stop negotiations with the Soviet Union, attack Cuba and thereafter spread the war. As a result of these feelings, the Soviet Union immediately went into a state of national alert.”

Later on, the files reveal the Kremlin’s first interaction with Oswald, during an earlier trip to the Soviet Union.

The documents cite a Soviet defector to the US, named Yuri I Nosenko, who told intelligence officials: “Oswald came to the attention of the KGB when he expressed a wish to defect to the Union of Soviet Socialist Republics shortly after his arrival in Russia.

“However the KGB, after enquiry, decided he was mentally unstable and informed him he had to return to the United States upon completion of his visit.

“Thereafter, when Oswald missed a sight-seeing tour he was to take, his hotel room was forced open and he was found with one of his wrists badly cut.”

The document notes that the KGB had not tried to recruit Oswald. The file says: “According to Nosenko, Oswald’s case was a routine one in which the KGB had no interest until he assassinated President Kennedy. He was not approached or recruited for espionage by the KGB.”

Meanwhile the files also revealed how the US hatched strange and spectacular plots to kill Fidel Castro.

The documents show just how strange and detailed those were — including plots to kill him off with a festering swimsuit.

Another plot saw spies discuss the possibility of planting a “spectacular seashell” to catch Castro’s attention. Once he swam towards it, the explosives inside would be set off and kill him, they suggested, but that plan was also abandoned after it was determined that there were no shells large enough in the Caribbean area for the plot.