BUENOS AIRES—A few weeks ago, Hilda Molina, a delicate, soft-spoken neurosurgeon, obtained an improbable victory against Cuba’s regime when she left Havana and joined her son and grandchildren in Argentina. Listening to her story in a Buenos Aires restaurant, I could not keep from thinking that the real measure of the Caribbean tyranny is not how it treats its enemies but its friends.

Molina was her country’s first female neurosurgeon. In 1989, she founded the International Center for Neurological Restoration. It quickly gained attention; by the early 1990s, Molina’s prestige in the scientific community was so great that Fidel Castro decided to use her politically. The party prevailed on her to become a deputy in the National Assembly, an activity she found “extremely boring” because she and her colleagues were “expected to rubber stamp” decisions made “upstairs.” She played along, she says, “for the sake of my vocation.”

Castro became a frequent visitor to her center—until in 1991 the health ministry informed Molina that she and her staff would have to devote their better efforts to treating foreigners able to pay in dollars at the expense of Cuban patients. When she protested, she was reminded that she had an elderly mother and a son, neurosurgeon Roberto Quinones. Understanding the threat, she advised Quinones to use the occasion of a professional trip overseas to defect. He did just that, settling in Argentina, where he and his Argentine-born wife eventually had two children.

With her son out of Cuba, Molina resigned her position at the center and her seat in the National Assembly, and returned all her medals. That was the beginning of a 15-year ordeal. She was the object of numerous “acts of repudiation”—pogrom-like aggressions against dissidents in Cuba—and constantly vilified by the authorities. When her grandchildren were born, she begged to be allowed to visit her family in Argentina—to no avail.

“My only comforts,” she says, “apart from my mother, were a few brave friends critical of the regime who helped me in the worst circumstances.” She became close with dissidents such as Dagoberto Valdes, Martha Beatriz Roque and the Ladies in White, as the relatives of 75 journalists and human rights activists jailed in 2003 are known.

A few years ago, when Argentine President Nestor Kirchner asked Castro to let Molina visit Buenos Aires, the dictator replied, “Never!” In a foreword to a book titled “Fidel, Bolivia y algo mas,” Castro accused Molina of being “excellent material for blackmail.” By then she had become an international cause celebre.

Castro claimed she was really interested in owning the neuroscience center for “capitalist exploitation,” a charge that begs the question: Had 50 years of communism not eradicated capitalist greed from the island? Then he accused her of cloaking a controversy about stem cell research under political pretexts, which begs the question: Had 50 years of communist rule not eradicated bourgeois morals?

She has also been criticized by a small minority of Cuban exiles in Miami because her center participated in some studies related to embryonic nerve tissue transplantation in search for a cure for Parkinson’s disease—a type of research also conducted in the United States, Britain, Sweden, Poland, Spain and Mexico, and done under a strict international protocol.

In 2008, her mother, in her 90s, was allowed to leave. Molina was sure she would never see her mother again. But the neurosurgeon, who recovered her Catholic faith some years ago, was eventually granted permission to travel, in part thanks to help from the Catholic Church (no, 50 years have not eradicated that either). She arrived in Argentina a few weeks ago.

To President Cristina Kirchner’s credit, the Argentine government, an ally of the carnivorous left that is itself attempting these days to restrict freedom of the press, has not placed limits on her—except that pro-Castro mobs harassed her during a recent visit to the Argentine Congress.

As I listened to Molina, I kept thinking that her story was not about the tragedy but about the perfect farce that is Cuba’s communism. What else can be said about a regime that reserves its medical institutions for capitalist dollars in the name of abolishing capitalism and that for 15 years, in the name of anti-imperialism, prevents a woman from crossing borders in order to join her son? Yes, one perfect farce.