By the late 1950s, the US was ambivalent in its support for Batista.
The governments of Cuba and the US had signed a military assistance pact 72 hours before Batista’s coup on March 10, 1952. Article 2 of the pact stated that the US would supply the Cuban government with arms for the purpose of “implementing defense plans under which the two governments will participate in missions important to the defense of the Western Hemisphere.” However, the pact provisions clearly stated that such military assistance was not to be used for “purposes other than those for which it was furnished” without prior consent of the US government.
It was now obvious that military equipment received under the military assistance pact was being used to fight what had become a civil war.
Applying this framework, US support of the Batista regime was clearly implied.
Arguing for the imposition of an arms embargo, many Cubans and Americans contended that the Batista regime was using American-made arms to counter the activities of those Cubans who wanted “to restore freedom and justice in their own country.” Once the Batista regime had been overthrown, they argued, the people of Cuba would feel that the US had been Batista’s partner in the murder of thousands of Cuba’s young people.
This group concentrated on finding ways to influence US public opinion against all arms shipments to Cuba, and on mobilizing influential members of Congress to take the message to the White House.
Eventually, after supporters of the embargo provided photocopies of documents proving that US arms were being shipped to Cuba, Secretary of State John Foster Dulles announced that Washington’s guidelines in supplying arms would be
the need of a country to have defense against possible aggression from without [and the need for] a normal police force….We don’t like to have a large shipment of arms, particularly of a large caliber…go where the purpose is to conduct a civil war.
As a result, in March 1958, an arms embargo was finally enacted.
To Batista the arms embargo meant that the US had assumed a “neutral position” vis-a-vis the Cuban conflict. And within the Cuban political context, such “neutrality” was equivalent to US withdrawal of support for Batista.
Actually, aside from an order for 1,950 Garand rifles from the US which was confiscated, arms seem to have continued arriving aboard unmarked planes.
Nevertheless, the arms embargo had great psychological impact in favor of the insurrection, and it came less than a month before the urban underground attempted a general strike on April 9, 1958.