And, as an afterthought, it would not be hard to keep submarines out of Cuban ports if that is what we decided to do. In 1961 we had them remove missiles from their island and went head to head with the USSR to do it. It is all a matter of political will and courage on the part of leadership. With today's group the courage is lacking.
Swedish Sub Sinks The USS Ronald Reagan (Video)
Apparently in exercises they can't even keep one from sinking our fleet flagship even when said flagship knew in advance that the sub was out there and that it would be launching an attack. Subs are not easy to find. Especially if they aren't where you expect them to be.