What made Portuguese to become very skilled navigators?

A major reason Europeans mounted sea voyages in the 1400s was to find shipping routes for easier trade with Asia for spices and textiles. Portugal made early advances in voyaging due to a longstanding maritime culture and a stable monarchy, as well as the leadership of Prince Henry the Navigator (1394-1460).

Explanation:

During the 15th and 16th centuries, Portuguese explorers were at the forefront of European overseas exploration, which led them to reach India, establish multiple trading posts in Asia and Africa, and settle what would become Brazil, creating one of the most powerful empires.

Hope this helps!

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