For more than 50 years, the US government's schemes to overthrow the Castro government were, if not successful, always creative: poisonous cigars, an exploding seashell and secret Twitter-like service in Cuba.
Barack Obama says the US will re-establish diplomatic ties with Cuba and bring change to the long-standing trade embargo. But it is unclear if all secret operations will cease.
Disclosures by The Associated Press this year revealed how the US Agency for International Development (USAID) continued Washington's stealthy democracy-promotion work as some politicians and others pressed for a return to normality with Cuba.
The White House's announcement of revived ties came hours after American Alan Gross, a USAID contractor, was freed after serving five years in a Cuban prison for smuggling communications technology. Meanwhile, USAID administrator Rajiv Shah said he was leaving his post early next year.
It was revealed this year that USAID secretly created a primitive social media programme called ZunZuneo, staged a health workshop to recruit activists and infiltrated Cuba's hip-hop community.
Those programmes were part of a campaign aimed at undermining the Castro government through the citizenry, rather than directly targeting political leaders. Yet they were still fraught with danger and incompetence.
Following the disclosures, USAID prepared internal rules that would effectively end the agency's risky undercover work in hostile countries. AP found USAID and its contractor, Creative Associates International, had concealed their involvement in the Cuban programmes by setting up front companies, routing money through overseas bank transactions and fashioning elaborate cover stories.
The aid agency's recent secret missions were the latest in a series of efforts by the US government - from presidents John F Kennedy to Barack Obama - that began shortly after Fidel Castro's rise to power in 1959.
Washington broke diplomatic relations two years later, around the time the doomed CIA-led Bay of Pigs invasion was launched to topple the new leader.
The US government was not deterred. The CIA considered a plan to kill Mr Castro by exploding an exotic seashell where he went diving, but it was deemed impractical. Another scheme, in 1960, was designed to inject poison into his favourite cigars, but nothing came of that either.
In more recent times Mr Gross, using backpacks and carry-on bags, smuggled secret communications equipment into Cuba to try to build an uncensored internet network purportedly for the island's small Jewish community. He was arrested, convicted and declared a spy by President Raul Castro.
USAID's recent Cuba programmes, although less dangerous than some past misadventures, received sharp criticism this year from some US politicians who called them "reckless", ''boneheaded" and "downright irresponsible".
Cuban artists swept up in the programme were detained or interrogated by Cuban authorities. The secret US hip-hop operation backfired after Cuban authorities found that an independent music festival - one of the largest on the island - was really backed by the Obama administration.
Others in Congress said, however, that they supported the aid agency's efforts, noting Cuba's human rights record and its repression against dissidents.
Congress directed USAID recently not to do work in politically repressive countries unless it could execute it with its own staff, and without extensive secrecy. In any event, any work by USAID in Cuba is illegal under Cuban law.
White House press secretary Josh Earnest said yesterday the administration would continue the democracy initiatives in Cuba that the Castro government has complained about.
"USAID programmes that have been in place and that have drawn the criticism of the Cuban regime will continue even after Dr Shah transitions out of his current job," he said.
It was not immediately clear how that would square with the new congressional directive about USAID's activities, passed in a year-end congressional spending bill.
Senior US officials said Dr Shah's departure was not linked to the fallout from his agency's once-secret Cuba programmes or to Mr Gross' release. But Dr Shah's resignation, billed as long in the works, came just hours before the president announced the policy change - and as Mr Gross was travelling back to his home country.
USAID's inspector general is reviewing whether the agency's recent Cuba programmes disclosed by AP were proper.
Ryan Goodman, a New York University law professor, said it was "difficult to fathom" how USAID's operations, such as ZunZuneo, were not covert actions that required additional legal sign-offs.
"Unless USAID has a better explanation," he said, "these programmes surely seem to fit the definition of covert action under US law."
The agency has denied the programmes were covert and maintains Congress was informed about them.
But last week, as the secret hip-hop programme made headlines, Senator Patrick Leahy, who leads an upper-house panel on foreign operations, contested USAID's assertions of transparency.
"USAID never informed Congress about this and should never have been associated with anything so incompetent and reckless," he said. "It's just plain stupid."