Just when Cuba was starting to warm up to the United States, Americans elected Donald Trump president, throwing the countries' rapprochement into doubt and causing stunned reactions in Havana.
The brash Republican billionaire's shock victory cast uncertainty over two years of moves by President Barack Obama to end more than a half-century of Cold War enmity with the communist island.
Trump has sent mixed messages about the thaw.
He gave it a lukewarm welcome at first, saying "50 years is enough" - although he characteristically insisted the Democratic president should have struck a "better deal." Then as the Republican primary heated up, he vowed to reverse the new policies unless the Raul Castro regime agrees to democratic reforms and other demands.
"I'm afraid," said Marcos Creach, a 27-year-old cell phone repairman in Havana.
"Obama did a lot" for US-Cuban relations, he added, and now Trump "can come in as president of the United States and put up a wall, an obstacle to make sure it never becomes reality." Creach counts himself among those Cubans who stand to benefit from resumed ties between Havana and Washington and a softening of trade and tourism restrictions - part of a new generation of entrepreneurs Obama said the thaw aims to help thrive.
Droves of Cubans descended on the capital's few Wi-Fi hotspots from the early hours Wednesday, trying to contact relatives in the United States to help make sense of the shock result.
Alison Taylor, an 18-year-old epidemiology student, worried Trump's proposed anti-immigration policies mean she will have a hard time reuniting with her boyfriend.
Two years ago, he joined the exodus across the Florida Straits that started with the Cuban Revolution in 1959.
"All Cubans dream of meeting their families (in the United States) someday," she said. "For many, it's been so long since they've seen them.
"I'm chatting with my boyfriend in New Jersey right now and we're talking about that, and how much it hurts." She called Trump's election "the worst thing that could have happened." "I think all Cubans feel that way," she said, calling Trump a "man with no scruples, a fascist, a horrible person." .
Cuba's government said in a terse note that President Castro sent his congratulations to Trump.
But it raised eyebrows when it published a notice Wednesday morning in the Communist Party's official newspaper, Granma, that it will hold military exercises from November 16 to 18.
The nationwide exercises would prepare to confront "the enemy," it said, employing its longstanding term for the United States.
Although Cuba has periodically held such exercises since 1980, the timing was conspicuous.
It is unclear how Trump as president will act on Cuba.
The US president-elect has been "ambivalent" about the issue, said political analyst Jorge Duany, director of the Cuban Research Institute at Florida International University.
But Trump's shift to a hardline stance - fending off attacks from primary challengers such as Cuban-American Senator Marco Rubio of Florida - probably helped him win that key swing state in the general election, Duany said.
"This new position probably won him a large part of the conservative Cuban-American vote in southern Florida." .
Obama enacted his signature Cuba rapprochement using executive authority.
Blocked from ending the US embargo on the island by a Republican-controlled Congress, he pushed smaller reforms through with the power of his presidential pen.
That means Trump can now change course just as easily, reinstating trade and financial restrictions and reversing developments like the resumption of air and cruise-ship travel, and postal service.
However, Cuba will probably not be a "priority issue" for Trump, said Michael Shifter, head of the Inter-American Dialogue, a Washington-based think tank.
"It's not clear if he will try to roll back policy toward Cuba that is fairly popular, according to polls," he said.
One thing is certain: with the Republicans retaining control of Congress, the 54-year-old embargo is probably not going away anytime soon.