I don't see how the one follows from the other. You're saying because there are big issues, solving what you seem to deem as a relatively small issue, therefore

I don't see how the one follows from the other. You're saying because there are big issues, solving what you seem to deem as a relatively small issue, therefore can't be deemed a significant success? If so, I'd invite you to look into the 200 year history of US-Cuban relations, as well as the extent to which the embargo affects virtually everything for a population of 11 million people. It's extremely pervasive. A change here would be quite a major foreign policy event. To get a sense of this, the UN general assembly condemned it for every single year without exception for decades now, with votes usually showing 180 or so in favor of condemning and 3 or so against (the US, Israel and something politically insignificant like Micronesia)