The crisis in Venezuela has spread to its closest ally Cuba, with Havana warning of power rationing and other shortages that some fear could mark a return to the economic austerity that traumatised the island nation after the collapse of the Soviet Union. Only a year after the euphoria that followed the re-establishment of diplomatic relations with the US, hopes of an economic rebound in Cuba have faded and an undercurrent of concern and frustration is evident on the streets of the capital.  “Just when we thought we were going forward, everything is slipping away again,” says Havana retiree Miriam Calabasa. “I am worried people are going to decide enough is enough: then what?”  Government offices now close early, with open windows and whirring fans in lieu of air-conditioners. Already scant public lighting has been reduced further, and traffic in Havana and other cities is down noticeably.