Documents released to the National Security Archive at George Washington University reveal that Fidel Castro feared an invasion of Cuba by the United States immediately following the assassination of President Kennedy.
Castro mobilized his armed forces in preparation.
“This caused Castro to wonder whether the assassin was … the mere instrument of a monstrous plot of American militarists, who, by eliminating Kennedy, would put (President) Johnson in a position from which there would be only one way out: to drain off anti-Cuba hysteria by an action of declared war,” the NSA reported.
It seems Castro came to this conclusion long before the bulk of assassination research had begun.
“Castro feared that the assassination would unleash passions and violent and blind hysteria of the American people against Cuba and Russia,” the NSA reported.
Castro seemed to have shared concerns with authors and researchers publishing years later that the assassination of Kennedy was a pretext for an invasion of Cuba, an escalation of tensions in Vietnam and the continuation of the cold war with the Soviet Union.
An invasion of Cuba never materialized, but evidence exists that this may have been a goal of some of the players within the coup.
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The Soviet reaction is almost exactly the same, as is reported by Walter Cronkite