Cuba is on the map, and as the CSA I would like to invade and conquer it. You are not allowed to declare war against Spain, and my troops aren't allowed in their country. I know that this is outside of the normal history, but there is historic evidence of the south's desire to obtain cuba.
There is historic precedent for this.
In 1851 Genral Narcisco Lopez invaded Cuba with 500 mercenaries from New Orleans, which was quickly crushed.
In 1860 there was an attempt by Southern politicians to purchase Cuba and add it as a slave state.
In 1861 CSA high command talked about invading cuba, but it was quickly abandon as being impractical.
A funny thing is that people who wanted to add Cuba were called filibusterers