In the case of Cuba I imagine it's simply just political control, vassalage, control of the hemisphere. In the case of Venezuela it is Energy Dominance. The USA wants to control Global Energy supplies: oil and [natural] gas. It's all about China. By controlling the world's energy supplies the USA hopes to curtail the rise of China as a peer competitor and prevent other nations from achieving that status as well. Oil is price in $US. Iran was selling their oil in Yuan. That's a big no no from the point of view of maintaining US Hegemony.
In the case of Cuba I imagine it's simply just political control, vassalage, control of the hemisphere. In the case of Venezuela it is Energy Dominance. The USA wants to control Global Energy supplies: oil and [natural] gas. It's all about China. By controlling the world's energy supplies the USA hopes to curtail the rise of China as a peer competitor and prevent other nations from achieving that status as well. Oil is price in $US. Iran was selling their oil in Yuan. That's a big no no from the point of view of maintaining US Hegemony.