It's not long after you leave Havana Airport that you realise why an improvement in relations between Cuba and the US is so important.
There, at the end of the road going away from the terminal, is a giant poster, the colours somewhat faded, showing a picture of Fidel Castro on one side and the now dead Venezuelan leader, Hugo Chavez, on the other. They are brothers, it declares.
And they were. Cuba's economy was kept afloat on Venezuelan oil. Before Venezuela it was Soviet aid that helped keep Cuba going.