Is Cuba really America’s most serious national security threat? You might think so from the sanctions the U.S. imposes on it, which are more onerous than those on Iran and North Korea.

Cuba is hardly benign. It beats and imprisons dissidents, commits aggressive espionage, cheers on Iran and Syria, and supports some of the Western Hemisphere’s most democratically challenged regimes. Still, it is fitfully changing for the better, and the U.S. can help speed along the process.

President Raul Castro, the 81-year-old brother of Fidel, has laid out plans for economic reform and is passing power to Cuba’s post-revolutionary generation. The impending demise of Hugo Chavez, whose country supplies Cuba with about two-thirds of its oil in a sugar-daddy barter arrangement, is another potential catalyst for change.

That said, there’s an even better reason to alter U.S. policy toward Cuba: It isn’t working. A half-century after John F. Kennedy slapped sanctions on the Castros, they’re still in power. The U.S. embargo has little global support; no other country puts sanctions on Cuba. Even more absurdly, sanctions that were first imposed to protest Castro’s expropriation of U.S. assets now keep most U.S. companies out of a Cuban market that is attracting increasing amounts of foreign investment. Although reliable numbers are elusive, one recent report estimated that total foreign investment rose to $3.5 billion in 2009 from $1.9 billion in 2001.

Meanwhile, the sanctions regime sucks up U.S. resources. From 2000 to 2006, the U.S. opened almost 11,000 Cuba sanctions investigations, versus almost 7,000 for all other countries combined.

The inflexible, maximalist nature of U.S. policy leaves the initiative for improvement almost entirely with the Cuban side. The infamous Helms-Burton legislation that passed in 1996 conditions any changes in U.S. sanctions on congressional recognition of a transition government in Cuba, and gives authority over the sanctions to Congress instead of the executive branch.

This approach feeds the Cuban regime’s narrative that it is locked in an uncompromising existential struggle. It also prevents closer cooperation on regional issues that both countries need to address, such as cleaning up oil spills and fighting drugs and terrorism.

With a Republican-controlled House of Representatives, a repeal of Helms-Burton is unlikely. President Barack Obama is not powerless, however. He has several opportunities to promote greater openness and reform -- if he’s willing to take some heat. Having won re-election with a big bump in his share of Florida’s Cuban-American vote, he has some political room to move.

The first thing Obama can do is take Cuba off the State Department’s list of State Sponsors of Terrorism. It no longer trains or arms revolutionary movements, and the U.S. intelligence community decided as far back as 1998 that Cuba posed no threat to national security. Indeed, compared with hostile, nuclear-weaponized regimes such as North Korea (taken off the list in 2008) or ostensible U.S. ally Pakistan (with its clandestine links to the Taliban and other violent jihadist groups), Cuba seems a beacon of peace. Removing it from the list would open new avenues of commerce. It might also break the stalemate over the case of Alan Gross, a U.S. contractor imprisoned in 2009 for distributing computer equipment to members of Cuba’s Jewish community.

In 2009 and 2011, the Obama administration wisely lifted some restrictions on travel and cash remittances. It can further encourage more direct contacts with the Cuban people by re-establishing ferry services, authorizing financial and technical help to small businesses, permitting Americans to donate and trade in goods and services with entrepreneurs and independent farmers and professionals, and expanding the licensing system for travel to Cuba. (If Dennis Rodman had tried to go to Cuba instead of North Korea, he might have had to wait months or years for permission from the U.S. government.)

The Obama administration also has a more immediate problem: Cuba’s decision to relax its emigration policy means that the U.S., which has long granted preferential treatment to Cuban refugees, may face a spike in new arrivals. Any effort at comprehensive immigration reform needs to take those changed circumstances into account.

Four years ago, the chairman of the Senate Foreign Relations Committee lamented U.S. policy toward Cuba. “After 50 years of failure,” he said, “it’s time to try something new.” That senator is now secretary of state. Let’s hope John Kerry remembers his words.

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