The Royal Navy.
Athens had a powerful navy.
The U.S. Navy, Royal Navy, U.S.S.R Navy.
Yes. They defeated the most powerful navy in the World. But how? The United States has the really powerful heart. They defeated the British navy by the end of the American Revolutionary War.
Britain had the most powerful navy until about world war 1 and now its probably America.
China has the largest if you count by "tonnage", although this does not automatically mean they have the most "powerful" navy. The US Navy is the most powerful in Asia, although it itself is not an Asian country.
The titanic was the most powerful ship...
Athens
The Invincible Armada
Athens
In World War 2, the Japanese wanted to move first against the US because they knew the US would eventually become involved. By attacking first, they were able to eliminate some of the USA's powerful navy.
China has the world's second most powerful navy called the People's Liberation Army Navy. It is composed of one aircraft carrier, three transports, 25 destroyers and 58 submarines.