Follow these blurry smoke signals to their origin, and you discover a few dozen men, slumped in rickety wooden chairs around a scattering of tables. Their faces are creased by (too) many years in the glare of the subtropical sun; the complexion of some resembles sun-dried tomatoes, that of others, crumpled cardboard.
The only sounds are the rapid clatter of dominoes and chess pieces, dancing around the tables; the occasional pained murmur at a rival's move; and the quiet crackle of a match, followed shortly by a half-cough, half-gurgle of contentment. Try to look closely at the absurdly-proportioned cigar that is now being drawn upon happily, and you will certainly be invading the smoker's personal space.
There are two reasons why these gentlemen do not want you to read the small disc an inch along the stem. The first is that it may not be a Havana cigar, and they fear losing face if you discover them smoking anything but the best. The second is that it may be a Havana cigar, and they fear you may be an undercover agent from the US Treasury, investigating their trade with the enemy.
Welcome to Little Havana, where none of the usual rules applies.
After a breezily inconsequential conversation with Guillermo (mid-fifties, complexion looking as though it had done time as Kenneth Clarke's footwear), I offered a parting remark: "Viva Cuba".
"No," he corrected, "Viva Cuba libre."
Guillermo was born in Havana in 1944. He was nine when Fidel Castro and a ragbag of revolutionaries launched a feeble attack on the Moncada Barracks in Santiago de Cuba (the government forces must have realised this would not be much of a contest when some of the guerillas arrived by taxi). He was 14 when the Batista regime collapsed and Fidel Castro came to power. "Big bandido", as Guillermo insists on calling him, except when he switches to the grumble "Castro loco".
As a young man, Guillermo became a fisherman at the port of Cojimar, where Hemingway set The Old Man and the Sea. Then life became tough.
When the United States gets angry, its revenge can be fierce. The US had plenty of reasons to be cross with Castro and his fellow revolutionary Che Guevara - who, almost as soon as the fighting stopped, had started to nationalise American enterprises. Then came the Bay of Pigs invasion, a bunch of 1,500 mercenaries and exiles who landed on the beach at a seaside resort in the south of the island, hoping to reverse the revolution. The whole shooting-match was sponsored by the CIA, but turned out to be about as successful as a sponsored walk into the sights of Fidel's forces. Castro declared himself a lifelong socialist, and a year later offered the island as a gun emplacement for Soviet nuclear missiles. President Kennedy was furious, and tightened the economic noose around Cuba. Which is why you can't legally buy Havana cigars in Miami, or anywhere else in the US. And why Guillermo decided, by 1968, that it was time to leave the privations of life on the Caribbean's largest island.
Guillermo was lucky, he says, in his choice of profession. As a pecador (the correct Spanish word is pescador, but Guillermo and his compatriots share a linguist disdain for consonants), he simply set sail one day and never came back. As a Cuban, he qualified automatically for life in the US. After immigration, he headed for Calle Ocho.
And that's where you are right now. Eighth Street has been a Latin quarter for a century, but adopted its Spanish translation when the rambling apartments and weatherworn bungalows began to fill with Cuban emigres after the revolution. Little Havana strings itself along Calle Ocho for a mile or so in an otherwise anonymous quadrant of Miami - equidistant between the shiny towers of downtown, the affluent malls of Coral Gables and the relentless din of the airport, and a world away from the glitzy South Beach beloved of Versace.
Today, in Havana, Cojimar and all over Cuba, the celebrations of Moncada Day - commemorating the failed attack on the barracks - will be long and lively. In Miami, the men will just carry on smoking and hoping, and pretending.
The hope, as expressed by Guillermo's call for "Free" Cuba, is that Fidel Castro will die or be deposed by a popular uprising. Then they can all go home, reclaim their property "liberated" after the revolution and open branches of McDonald's; a highly Hispanic branch, looking like a prototype for Havana, stands on a street corner. (The street in question, by the way, is named Captains Padron, Perez and Sosa Way; all those who have helped in the struggle against Castro are commemorated, though sometimes it's three to a signpost.)
Some are doing more than hoping: Miami is the headquarters for a range of anti-Castro organisations, such as the shadowy Alpha '66 mob who hold regular weapons training, and direct-action groups possibly including the bunch which bombed two Havana hotels a fortnight ago; the plan was to disrupt tourism, the industry upon which Cuba now depends.
The pretence is that Little Havana resembles its role model. There are, of course, similarities: in both Miami and Havana, the taxi drivers are Cuban, with a poor grasp of geography, of English and of driving. But the cars in Havana are mostly huge old American vehicles, while Miami is full of small, new Japanese models. And while Havana has its share of monuments, it is not thoroughly stuffed with memorials like Calle Ocho.
The most notable is a flame, elevated on a cenotaph and protected by two rings of chain, one mounted on empty shell casings. It burns eternally to the memory of fallen martyrs; specifically, los Martires de la Brigada de Asalto 2506. The date gives the game away: 17 April 1961, the day the Bay of Pigs ran red with the blood of doomed invaders. One of the survivors was the father of Gloria Estefan, the singer whose music is wafting out of the Cafeteria Exquisito.
This part of Miami's Havana Experience is better than the real thing: a cafe selling real mezclado, the hot, sweet, strong shot of coffee - just what you need, but can rarely find, to propel you through a heavy Havana afternoon. While here, tuck into morros y cristianos (black beans and rice), amplified with spicy pork. Another giveaway - this is far tastier than anything in real Havana.
Refreshed, you can take in another tranche of memorabilia, such as the massive relief map of Cuba, the size and shape of a large alligator. Someone has drenched it with paint, and chipped away the last letters of a quote from Jose Marti, the 19th-century leader of Cuba's independence movement: "Fatherland means agony" - expressing the pain of the battle for self-determination.
The symbolism continues as relentlessly as one of Fidel's famous five- hour speeches. As pointedly political art goes, the 50ft mural at the Parque Mximo Gmez takes some beating. It was painted a couple of years ago, to celebrate the Summit of the Americas. Every significant nation in the hemisphere is represented, with one weighty exception: Cuba. Yet every man currently in the park was born on the island - apart from me, that is, though the longer I spend in Little Havana, the more Cuban I feel.
The imposing Tower Theatre is being refurbished to its former Thirties glory. An artist's impression shows how its Art Deco features will be accentuated. To make it look like a working cinema, someone has dreamed up a film title: La Cuba de Ayer - the Cuba of yesterday. But Cuba was never quite like this.
"Life," says the sign dangling above Calle Ocho outside the Renaissance Cigar Company, "is too short to smoke a bad cigar." I hope life is long enough for Guillermo and his chums to go home, and that the city they find is big enough for all of them. Meanwhile, they will continue to wheeze away their lives in exile on Main Street, USA.
To reach Little Havana, fly from Heathrow on American Airlines (0345 789789), British Airways (0345 222111) or Virgin Atlantic (01293 747747); or BA or Laker Airways (01293 789000) from Gatwick. A cab from Miami airport to Little Havana costs $8 (pounds 5) or less, including tip.Reuse content