Che Guevara
In Guevara's private writings from this time (since released), he displays his growing criticism of the Soviet political economy, believing that the Soviets had "forgotten Marx". This led Guevara to denounce a range of Soviet practices including what he saw as their attempt to "air-brush the inherent violence of class struggle integral to the transition from capitalism to socialism", their "dangerous" policy of peaceful co-existence with the United States, their failure to push for a "change in consciousness" towards the idea of work, and their attempt to "liberalize" the socialist economy. Guevara wanted the complete elimination of money, interest, commodity production, the market economy, and "mercantile relationships": all conditions that the Soviets argued would only disappear when world communism was achieved. Disagreeing with this incrementalist approach, Guevara criticized the "Soviet Manual of Political Economy", correctly predicting that if USSR did not abolish the law of value (as Guevara desired), it would eventually return to capitalism.
Marxism
In 1959, the Cuban Revolution led to the victory of Fidel Castro and his July 26 Movement. Although the revolution was not explicitly socialist, upon victory Castro ascended to the position of Prime Minister and adopted the Leninist model of socialist development, forging an alliance with the Soviet Union. One of the leaders of the revolution, the Argentine Marxist revolutionary Che Guevara (1928–1967), subsequently went on to aid revolutionary socialist movements in Congo-Kinshasa and Bolivia, eventually being killed by the Bolivian government, possibly on the orders of the Central Intelligence Agency (CIA), though the CIA agent sent to search for Guevara, Felix Rodriguez, expressed a desire to keep him alive as a possible bargaining tool with the Cuban government. He would posthumously go on to become an internationally recognised icon.