Dilma Rousseff, the Brazilian president, spoke for many when she remarked last week that US President Barack Obama’s move to improve relations with Cuba was “a moment that marks a change in civilisation”.

For more than half a century, Washington’s squeeze on Havana has poisoned its relations with the region. It often led even US allies to take the side of the Castro brothers, under the rubric that “Washington may be my friend, but they are my brothers”. Mutual US-Cuban hostility also widened hemispheric fractures. The two countries took opposite sides in Central America in the 1980s and, in 1971, a visit to Chile by Fidel Castro foreshadowed Augusto Pinochet’s US-supported coup. Today, however, detente between US and Cuba has the potential to force a profound realignment of American relations.

Rapprochement vaporises a rhetorical bludgeon that US critics have routinely used to cudgel Washington. That is especially important given China’s growing regional presence. It also helps to neutralise anti-US sentiment routinely wheeled out to mask local failings. At next year’s Summit of the Americas in Panama, which both the US and Cuba will attend, Latin Americans will now hopefully focus more on Cuba’s baleful human rights record.