Squeezed among the usual crowd of sleek young Cubans and paunchy, prowling European tourists, the owner of one of New York's hippest restaurants discusses his new Havana boutique hotel project. At the bar, a Swiss venture capitalist describes meeting with Communist Party officials about partnering on a marina complex. An Ohio woman who runs a bespoke guide service for wealthy Americans shows her clients iPhone photos of the private villa where they'll have a waterfront paella dinner the next day.

The foreigners visiting Havana used to be Canadians and Europeans on cheap beach package tours and left-leaning Americans on dutiful rounds of organic farms and neighborhood health clinics. Ten months after the U.S. and Cuba declared the end of a half-century of official hostility, the mood in Havana has changed.