What does it mean when a warship flies the pirate flag?

One reason is that the warship has been occupied by pirates and has officially joined the ranks of the green forest.

The other reason is the dual identity of the ship. For example, in the United Kingdom during the Age of Discovery, the British The royal family funded sailors and fleets to plunder Spanish merchant ships and share the profits. British ships usually seemed to be quite serious, but when they saw Spanish merchant ships, they turned into pirates. Because they flew the pirate flag instead of the British flag. , there is no proof. Captain Drake, the famous British hero, was actually a pirate leader.

The same is true for French pirates in the Caribbean, who also received domestic support and plundered merchant ships and ports of other countries. But There are also "mad dogs" who want their owners, no matter which country's flag they fly, they will snatch them all, and eventually they will be wanted by the fleets of various countries and live in exile in the tropical islands of the Caribbean.

If you are talking about American warships If so, it would be like this:

This is a tradition of the U.S. Navy. When warships sail across the equator, they fly the "Jolly Roger"

That's all.