IT was presented to the world as a tearing down of barriers, a historic moment of reconciliation between the United States and Cuba’s communist government after half a century of hostility. But inside a small villa a stone’s throw from Calle Ocho in the heart of Miami’s Little Havana neighbourhood the talk is only of one word — betrayal.

The house is the Bay of Pigs museum and library where the ageing survivors of Brigade 2506, the CIA-trained fighting unit that failed to topple Fidel Castro in an ill-fated — and many say ill-advised — 1961 invasion, gather to discuss the affairs of their homeland.

More than five decades after the three-day conflict, which resulted in almost 120 of the invaders dying and 1,200 captured by Castro’s forces when the US failed to deliver promised air support, the veterans are no longer the youthful and idealistic alliance of students, lawyers, bankers, former Cuban army soldiers and assorted others they once were.

At the last count, fewer than 900 were still alive, most now in their 70s and 80s. But while age may have slowed them physically, there remains much fire in their hard-line opposition to the Marxist revolutionaries still running Cuba. And now, after last week’s extraordinary deal between the US president, Barack Obama, and the Cuban leader, Raúl Castro, Fidel’s brother, there is plenty of sadness too.

“The brigade members have been betrayed twice, once in April 1961, and now in December 2014,” said Julio González-Rebull, 78, who flew combat and resupply missions aboard a B-26 bomber from the assault team’s base in Guatemala during the failed invasion.

“There is not a group of free Cubans anywhere in the world hurting like we are. Two American presidents have betrayed us, John F. Kennedy and now Mr Obama. I’ve not felt this sad for a very long time. Nothing has changed in Cuba. All the promises have come to nothing. I don’t know where things go from here,” he said.

His disillusionment is shared by others at the museum, an elegant building in a quiet residential street that has served as de facto clubhouse for Bay of Pigs veterans for almost 30 years. Inside, thousands of books and magazines, in Spanish and English, detail every moment of 20th century Cuban history, weaponry. Uniforms from the conflict are displayed in glass cabinets and portraits of the “martyrs” of Brigade 2506, and those who have died since, adorn the walls.

“We’re doing business with a guy who gave the order to shoot down those aeroplanes?” said another Cuban-American exile, who wanted to be known only by his first name Pablo.

Pablo was referring to a 1996 incident in which the Cuban air force destroyed two small planes belonging to the civilian-activist group Brothers to the Rescue in international waters 70 miles from Florida, killing four Cuban-Americans.

“If you think that anything’s changed here, forget it. The ones that exploited the people before, the politicians and cronies, will be the ones that profit, and the rest? Screw them,” Pablo said. “Tomorrow Castro will die and his son will take over. The owners of the farm are the ones who are running the farm.”

Perhaps the most significant item of memorabilia in the museum is the large yellow Brigade 2506 flag, presented to President Kennedy in a ceremony at Miami’s Orange Bowl stadium in December 1962 when the remaining 1,113 prisoners of war were released by a gleeful Fidel Castro in return for $53 million in US medicine and food.

In welcoming the prisoners home, Kennedy assured the large crowd, that “this flag will be returned to this brigade in a free Havana,” yet since the museum opened 28 years ago, it has remained enclosed in a glass case on the wall.

“When we met JFK at the Orange Bowl I believed we would have a second chance,” said González-Rebull, who lost his closest friend on the beach at GirUn, the brigade’s main landing site. “But it never happened. We carried on believing, but that opportunity never came.

“I’m sad now not for us, we are old people, but for those who don’t know. The Cuban people believe their style of life will get better but that’s a lie. I don’t know how people think things will change,” González-Rebull said. “I was sad that when Obama started his speech it was about the opportunities for Cubans, and for Americans to sell to Cubans. Where were the words about freedom, and liberty and human rights?”

Changes, meanwhile, are under way to preserve the veterans’ legacy in Miami. Work has started to build a new museum in Hialeah Gardens, funded by a $1m state grant, to which all the Brigade 2506 artefacts and memorabilia will be relocated next year.

González-Rebull said it was important that the story of the invasion continued to be told long after the last survivors had died.

“One of the saddest things for me was when we were invited to Congress on the 50th anniversary and some of them didn’t even know about April 17th 1961,” he said. “It was a long time ago, but the pain comes back. It’s a very emotional time for us.”

—By arrangement with the Guardian

Published in Dawn, December 25th, 2014