What was sir Francis Drake's last destination in his exploration route?

To the Caribbean

Explanation:

During Sir Francis Drake’s final voyage to the Caribbean to raid Spanish possessions, the fleet he commanded was decimated by a fever. He died from fever, or possibly dysentery associated with the condition, at sea on January 28, 1596, near Portobelo, Panama . He was buried at sea, supposedly in a lead coffin.

so, based on the research i've done. the u.s. government were always on a wild goose chase just to take down castro. he then retired his trone to his brother raul in 2008 due to some health issues. so it's obvious your answer would be:

castro had no allies from which he could receive aid.

hope this and have a fantastic day!

                                                    -wolfiewolffromsketch