Americans have been able to go to Cuba easily, but illegally for quite a while. We met a nice middle class older couple about 5 yrs ago who had just returned from Cuba. They lived in Arizona and had flown to Mexico City, then on to Havana. Maybe US intelligence knew, or maybe not. I have met others who have simply gone to Canada and flown out of Toronto.
My wife went 5 yrs ago on an academic junket. Not as simple as just purchasing a ticket, going to the airport and getting on a plane. Not even the State Department could tell her for certain until the evening before the travel date whether the group would even be going. I trust that sort of thing will change, especially if credit card usage will be allowed (as I have heard). I also heard that the travel industry is planning for changes that will occur within weeks, rather than months.