Seventeen countries had joined the ranks of the United Nations that very year, most of them from Africa. Both the United States and Cuba were looking to reach out to these newly freed states, and both recognized racism to be an acute factor at play. In the longest speech ever delivered at the United Nations, Castro transitioned seamlessly from his hotel experience, to the discrimination faced by North American blacks, to the broader evils of “imperialist financial capital” and the “colonial yoke.” (Castro would later add substance to this attention-grabbing profession of solidarity when he sent Cuban troops to fight white supremacist forces backed by the CIA in Angola.) During the same session, the U.S. delegation lamented that “all the explaining and apologies in the world will not erase the injury to an African delegate who is turned away from a restaurant.”

The blatant contradictions of the United States’s position were not lost on American activists. When the embargo of Cuban sugar was offset by an increase in the import quota from Apartheid South Africa the following year, the American Negro Leadership Council on Africa—whose executive board included Martin Luther King, Jr., Dorothy Height, and A. Philip Randolph—brought its objections directly to the secretary of state. Dorothy Day, Bayard Rustin, and Harlem’s own James Baldwin were among those to violate the United States’s ban on food and drug shipments to the Caribbean island. Once relations between the two countries had been frozen, Cuba’s delegate to the United Nations read a statement written by Robert F. Williams—a North Carolina NAACP leader who had visited Cuba and met with Castro in Harlem—demanding that the United States arm southern blacks.

Cuba’s willingness to exploit the United States’s contradictory foreign policy position and domestic racial turmoil helped spur the White House to resort to terrorism and other illegal, covert reprisals against the island nation. It also reinforced the repressive instincts already being brought to bear against American blacks. Ten days after Martin Luther King, Jr. denounced the botched Bay of Pigs invasion as “a disservice … to the whole of humanity” and called on the United States to “join the revolution” against “colonialism, reactionary dictatorship, and systems of exploitation” the world over, the Senate convened a committee investigating Cuban influence on American blacks. As the historian Suzanna Reiss explains in We Sell Drugs, the “narrative of criminality” that would later serve as the foundation for Richard Nixon’s declaration of the War on Drugs simultaneously sought to cast drug abuse as a form of chemical warfare being deployed against the United States by foreign communist forces (and Cuban forces specifically) and to tie homegrown civil rights advocacy to drug use and anti-capitalist “subversion.”

Castro’s accusations of hypocrisy would grow less credible as the civil rights situation improved in the United States and worsened under his regime. But this dynamic never fully went away. America would be more credible in maintaining its posture if it were not, at the same time, supporting far more egregious examples of despotism elsewhere. It would help, too, for a country with the largest prison population of any on the planet, both proportionally and absolutely, to ease up on the pretense that it is targeting Cuba over its abuse of “human rights.” In 1961, reflecting on racial unrest and the deepening conflict with Cuba, Martin Luther King, Jr. predicted that a failure to embody the “revolutionary spirit that characterized the birth of our nation” would leave the United States “with no real moral voice to speak to the conscience of humanity.” Echoing his sentiment five decades later, a Cuban commentator wrote at the height of the 2014 Ferguson protests, “Now, as in times past, we can see the brutal segregation and abysmal inequality for blacks and immigrants, in housing, education, work, [and] public health, among other human rights violations in the so-called most democratic nation in the world.”

And you don’t have to sympathize with the Cuban revolution or its oppressive regime to understand how obstinate hostility towards it has become a diplomatic deadweight for the United States. More than a half-century after the Cuban Missile Crisis, the entire world is united in opposing the embargo. Even the Latin American right, for which the specter of a revolutionary domino effect was once sufficient grounds to perpetrate social cleansing, has come to see political isolation as a counterproductive strategy, undermining the very reforms the U.S. says it would like to see. Obama’s efforts to set relations on a more constructive path have been met with an outpouring of goodwill, for him and the country, but Congress will have to walk down it if the embargo is to be lifted. At this point, alienating Cuba only alienates the United States. Punishing its people damages the United States’s credibility more than the Cuban government’s.