Which was an early event in the cold war?
a. china continued to threaten an invasion of japan
b. east germany formed an alliance with the soviet union
c. the united states refused to include russia in the marshall plan.
d. stalin kept troops in eastern europe instead of holding promised elections

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