In the wake of the bay of pigs invasion, tensions

 Tensions increased between Cuba and the United States.

Context/explanation:

The Bay of Pigs invasion was a foreign policy embarrassment for the USA during the Kennedy administration. The invasion was carried out by Cuban exiles that had been trained by the United States' Central Intelligence Agency (CIA).  Within just three days in April, 1961, the force of exiles invading at the Bay of Pigs was soundly defeated by the Cuban Revolutionary Armed Forces, commanded by Cuba's communist leader Fidel Castro.   The CIA-trained force of Cuban exiles sought to overthrow Castro's government. 

In the aftermath of the Bay of Pigs affair, Cuba requested that the USSR, as its communist sponsor, place missiles in Cuba to deter further US-sponsored action against the Castro regime.  That request, coupled with the fact of American missiles that were located in Europe, within striking distance of the USSR, prompted Nikita Khrushchev of the USSR to send the missiles to Cuba.  And that became the "Cuban Missile Crisis" of 1962. 

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the hereditary right of a monarch to rule from the mandate of heaven