http://www.bbc.co.uk/news/magazine-19930260
Cuban missile crisis: The other, secret oneContrary to popular belief, the Cuban missile crisis did not end with the agreement between the US and Soviet Union in October, 1962. Unknown to the US at the time, there were 100 other nuclear weapons also in the hands of Cuba, sparking a frantic - and ingenious - Russian mission to recover them.
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Fearing that Castro's hurt pride and widespread Cuban indignation over the concessions Khrushchev had made to Kennedy, might lead to a breakdown of the agreement between the superpowers, the Soviet leader concocted a plan to give Castro a consolation prize.
The prize was an offer to give Cuba more than 100 tactical nuclear weapons that had been shipped to Cuba along with the long-range missiles, but which crucially had passed completely under the radar of US intelligence.
Khrushchev concluded that because the Americans hadn't listed the missiles on their list of demands, the Soviet Union's interests would be well served by keeping them in Cuba.
Kremlin number two, Anastas Mikoyan, was charged with making the trip to Havana, principally to calm Castro down and make him what seemed like an offer he couldn't refuse.
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In the weeks that followed, Mikoyan kept the detail of the missile transfer to himself while he witnessed the mood swings and paranoia of the Cuban leader convinced that Moscow had sold Cuba's defence down the river.
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He then extricated Moscow from a seemingly intractable situation which risked blowing the entire crisis back up in the faces of Kennedy and Khrushchev.
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On 22 November 1962, during a tense, four-hour meeting, Mikoyan was forced to use the dark arts of diplomacy to convince Castro that despite Moscow's best intentions, it would be in breach of an unpublished Soviet law (which didn't actually exist) to transfer the missiles permanently into Cuban hands and provide them with an independent nuclear deterrent.
Finally after Mikoyan's trump card, Castro was forced to give way and - much to the relief of Khrushchev and the whole Soviet government - the tactical nuclear weapons were finally crated and returned by sea back to the Soviet Union during December 1962.