How would Congress and the President react to the knowledge that Cuba possessed deliverable weapons of mass destruction? Undoubtedly this knowledge of an existential threat would command all of our ingenuity to be resolved before any other issues of the day.
Stop the threat of a nuclear Iran over Israel.
Why is this important?
If Cuba were to acquire nuclear weapons of mass destruction right on our doorstep, then it would bring home the urgency of having to deal with this life threatening issue of national security over all other issues of the day.
Then we would perhaps feel the urgency that our ally Israel feels every day to resolve the nuclear threat that is being imposed on it by Iran.