Pirates as "the enemy of all mankind"

In Black Flag, Black Ship, I wanted my heroes to face world class-antagonists. I didn't want to use garden variety puddle pirates, thank you.  I really wanted them to be truly awful and very lethal  folk.

While reading Captain Charles Johnson's A General History of Pyrates, from Their first Rise and Settlement in the Island of Providence, to the present Time, I came across an abstract of English anti-piracy law. In it pirates were declared the enemy of all mankind, hostis humani generis for those with a legal turn of mind. Sound like anyone you've heard of before?

"You are of your father the devil, and you want to do the desires of your father. He was a murderer from the beginning, and does not stand in the truth because there is no truth in him. Whenever he speaks a lie, he speaks from his own nature, for he is a liar and the father of lies".

John 8:44

Be of sober spirit, be on the alert. Your adversary, the devil, prowls around like a roaring lion, seeking someone to devour.
1 Peter 5:8

The scourge of piracy with its demonic influence has plagued civilization for thousands of years.  Rome after its wars with Carthage rose to become  the dominant naval power in the Mediterranean Sea and piracy was held at bay.

Julius Caesar as a young boy was kidnapped by pirates and held for ransom. When told they were ransoming him for 20 talents of silver, Julius was highly insulted and told them he was worth 50 talents of silver. Throughout his captivity young Julius told his captors that he intended to come back and crucify the lot of them. After his family paid the 50 talents, he did return with his own fleet and so he did execute them in that  particularly gruesome Roman manner.

 But when Rome fell, piracy returned.  Throughout world history and in every part of the world, whenever civilization's grip weakened, piracy manifested itself.

In the year 1700, pirates were active throughout the world, plaguing every people group. Various forms of insurance were formed in response to that very real threat of loss by pirates. The Dutch and the English were among the first Europeans to insure cargoes and vessels against loss.

Like sharks following schools of tuna, pirates learned to pick critical choke points where long distance European traders had to pass.  Pirates of this time were especially active in the Mediterranean, the Caribbean,  off the coasts of North America and West Africa, and in the Indian Ocean.

At this time, European navies were fairly small  with a limited patrol range. Standing armies and navies were not the norm.  To augment their smaller forces, countries would lease privately-owned vessels for a short time and staff with their own sailors, or preferably give the the owners the opportunity to crew their own vessels and attack enemy shipping under a legal contract called a letter of marque.

This warrant allowed  private citizens to cross their borders and attack those parties specified in the letter of marque.  It was not uncommon for enterprising privateers to get letters of marque from several countries. Those who engaged in this form of warfare were called privateers because they operated a private warship on behalf of a a contracting country. Privateers brought captured ships and cargo back to a friendly port where prize courts assessed the value of the booty and awarded to the privateers a portion of the assessed value as prize money .

Occasionally, when pickings were particularly slim, privateers would go rouge and become pirates, as the English accused pirate-hunter Captain Kidd of doing. This usually happened during peacetime, when navies returned to their regular size and privateers and former navy sailors had to find new ways to support themselves.

During these periods, sailors would sign on for the duration of a pirate voyage and then move on to the next opportunity. Pirate crews came from many countries and it was not uncommon to have a crew with no common language. The picture that emerges is not that of a disorganized group of ruffians, but that of highly-skilled, sea-going mercenaries who knew their jobs so well they could work alongside those who didn't speak their own language.

With the danger inherent in piracy, pirates simply were in it for short-term gain without any real thought for the future. Sailors and pirates alike often blew their wages in spectacular ways while in port and had to return to the sea to stay alive.  As such, pirates only flourished when naval power diminished and governments tolerated their existence.

But what if a particular group of pirates had a long term goal and the means to achieve that aim?