Cuban migrants wait to enter a provisional shelter in Paso Canoas, near Panama's border with Costa Rica. (Carlos Jasso/Reuters)

President Obama has repeatedly decried the U.S. trade embargo against Cuba’s communist regime, most recently during his just-concluded visit to the island.

Yet his administration insists it has no plans to reconsider a half-century-old law that’s arguably more counterproductive with respect to political and economic change on the island: the Cuban Adjustment Act.

Signed by President Lyndon B. Johnson in 1966, the act offered Cubans haven in America on much easier terms than those available to people fleeing other repressive or impoverished nations, in recognition of the uniquely totalitarian system Fidel Castro built. Cubans who reach U.S. soil and stay for a year get legal residency, without the usual immigrant visa application and regardless of how they arrive.

Over the years, the Cuban Adjustment Act has been a magnet for thousands escaping the grim realities of Cuba — even if it means risking one’s life in a flimsy boat on the Caribbean Sea. Under the United States’ “wet foot, dry foot” policy, adopted after negotiations with Cuba to end a migration crisis 22 years ago, rafters intercepted by the Coast Guard on the water may be returned to Cuba, but those who make it to U.S. shores can stay.

Just three days before Obama arrived in Havana, a cruise ship rescued 18 starving and dehydrated Cubans packed into a 30 foot boat about 130 miles west of Naples, Fla.; nine others had died at sea.

The Castro regime blames these deaths on the Cuban Adjustment Act and demands its repeal — but this is pure hypocrisy. People would never take such risks if life under Cuban communism was bearable. The hundreds of thousands of Cubans who have left since 1959 bespeak the failure of the “Revolution.” And though Havana cannot admit it, the Cuban Adjustment Act probably helps stabilize the Cuban regime.

Emigration has served as a safety valve, enabling the regime to export the discontent it produces so efficiently.

To the extent Cubans are focused on leaving their country — and as anyone who has visited Cuba can tell you, dreaming and scheming to get out, not baseball, is the people’s true obsession — they are not focused on resisting its repressive system.

Many try the limited regular channels such as applying for one of the 20,000 immigrant visas the United States offers each year, or for political asylum in the United States or elsewhere. The regime’s control of passports, criminal records and other necessary documents gives it day-to-day leverage over these people while they wait, sometimes for years.

For many others, though, the prospect of legal residency under the Cuban Adjustment Act tips the risk-benefit balance in favor of the expensive, hazardous extra-legal voyage via the sea or overland through Latin America.

Once in the U.S., Cubans send back hundreds of millions of dollars in remittances, which help to pacify an otherwise restless populace and from which the government takes a cut.

Under recent travel liberalization by both the United States and Cuba, many Cubans have used the Cuban Adjustment Act to settle in South Florida, engage in Medicare fraud and other scams, then return to the island with the money, according to a Sun-Sentinel newspaper investigation. Many of those dollars wind up in regime coffers as well.

On balance, the Cuban Adjustment Act encourages individual Cubans to escape poverty and repression , and helps them do so, even as it enables the Cuban regime to continue impoverishing and repressing society as a whole.

Sooner or later, therefore, the Cuban Adjustment Act must change if Cuba is to change. But it won’t be easy to reform or repeal such a measure. The moment Obama, or a successor, asked Congress to change the law, there would be a chaotic rush to the exits in Cuba as thousands tried to get out while the getting was still good.

In fact, Cubans already fear that U.S.-Cuba normalization portends the Cuban Adjustment Act’s end; as a result, the Coast Guard reports “a steady increase in illegal maritime migration attempts from Cuba to the southeastern U.S.”

As the late Albert O. Hirschman explained in his classic work of social theory, members of a dysfunctional organization or society must constantly weigh three options: leaving, trying to change it from within, and swallowing their objections. Or, as the book’s title put it: “Exit, Voice and Loyalty.”

The United States needs a new immigration policy that’s still generous toward Cubans but better focused on the regime’s neediest victims — and that helps Cubans put domestic political pressure on Raul Castro’s regime, not just escape it.

Unable to inspire the Cuban people’s loyalty, and less able to manipulate their yearning for exit, Castro, or his successors, might finally have to heed their voices.

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