Tampa / St. Pete's FL. newspaper (has a searchable site) had a story a few years ago where someone sailed to Cuba came back. dude was arrested, boat impounded, legal issues were detailed ; vaguely remember it was settled don't remember the outcome, but it was not cheap.
there were cruisers who went yearly this case stopped them from going.
Pepsi Cola and Kentucky Fried Chicken did more to break the USSR than Raygun ever could. When we learn from History...