There was a legal difference between Pirates and Privateers. States granted letters of Marque and Reprisal to ship captains to engage in piracy against the state’s enemies. The state provided safe harbors to the Privateer.

Piracy was a difficult problem, but legalized privateering could severly damage internatioanl trade. State Sponsorship amplifies the power of non-state actors.

Criminal operate best with about 70-80 persons, a typical size for a mafia organization. If they grow larger, they are more likely to be destroyed by police forces. However, in the absence of a government, or with the actual support of governments, a larger number of individuals can cooperate.

Pirates, prior to the 19th century, appeared to be a permanent fact of life, much like slavery. Imperial navies periodically swatted some pirates, but pirates were like flies in a swamp.

The Caribbean Sea and the Mediterranean Sea were the worst hotspots. The North African Muslim states sponsored piracy against Europeans, while the Caribbean islands were often lawless. The major European powers used pirates as leverage when they waged war against other European powers. The British used privateering to weaken the Spanish Empire. Similarly, the United States became independent by sponsoring pirates against the British.

While no one kept detailed records of the total number of piracy attacks of that period, we can estimate the damage caused by looking at insurance records, namely the Lloyds of London. Insurance companies measured risk and probabilty of safe sea travel. Some risks were constant, like storms. Others varied depending on human agency. Insurance rates rose when ships passed through the Caribbean Islands, as pirate attacks were frequent. They also rose during periods of warfare.

The vast majority of pirate organizations operated with a single ship and engaged in minor captures. Pirates would never advertise themselves as pirates. Instead they collected intelligence about merchant activity in major ports. After a merchant ship departed, the pirate would pursue and capture the ship within a day’s travel from land. It was unlikely that they could capture a ship in the middle of the ocean. Nearly all pirate activity was located near shores and ports where ships were most likely to come into contact.

Pirates used some of the faster ships of the period. Typically they used a sloop-of-war or corvettes. A sloop carried 18-20 cannons, allowing pirates to outgun most lightly armed merchant ships. The sloop was a very fast warship favored by smugglers and privateers. It could quickly catch cargo-loaded merchant ships and outrun Naval Frigates. The Sloops needed a crew of 75 men, so it was at an optimal size for a small criminal organization.

Navies often used heavier ships. The Ships of the Line could have a hundred or more guns but were slugs at sea. The Frigate was a balanced ship, carrying 35 cannons and could move at a reasonable speed. The heavier ships outclassed pirate sloops, but could never catch them. Imperial navies were forced to use on sloops and corvettes to hunt pirate sloops and escort merchant ships. This nullified any advantages in gunfights between pirates and navies.

The real way to eliminate pirates was to go on land to arrest and execute them. States had to restore law and order at harbors and islands to truly reduce piracy.

Pirate ships usually operated independently. Blackbeard had a small fleet of 4 ships for a few months, but that was as large as pirate organization could grow before national navies destroyed them. At their worst, pirates could capture a few hundred ships over a period of decades. Llyods of London raised the insurance rates to compensate for the increased risk when merchants traveled through hotspots like the Caribbean Windward Passage or the North African coast. Individual pirates, however dangerous, were not a critical threat to nations. Many merchant ships placed a dozen or more cannons onto their top deck and would fight off pirate attacks on their own.

Organized piracy, called privateering, could seriously disrupt overseas trade routes. Rival nations in Europe and the USA granted Letters of Marque and Reprisal to pirates, hiring them as mercenaries. So the US, for instance, would tell ‘privateers’ to attack and rob British merchant ships during periods of war.

Safe harbor amplified piracy damage significantly. State sponsorship gave privateers free passage in the state’s territory. They could safely dock at the harbors, legally recruit sailors, and resupply their ships without legal interference. Pirates, in comparison, lived in secrecy

In the War of 1812, Congress granted these letters of Marque and Reprisal to pirates. Since the US could not fight directly against the British Royal Navy, it contracted privateers to engage in asymmetrical warfare against British merchant ships. Over 500 privateers were organized and granted funding, supplies, and safe harbor by the US government. Between 1812-1814, those privateers coordinated their activities with the US and captured or destroyed 1,350 British merchant ships. Lloyds of London to halted insurance of all merchants not traveling in naval convoy. This disruption in trade turned out to be the principal reason why the British gave the Americans relatively favorable peace terms.

The only way to guard against intense and widespread privateering was convoys. A large group of 20 or more merchant ships would travel under escort of a half-dozen or so frigates and corvettes. This slowed commerce even if they did not come under attack.

There are stong similarities between privateers in the 18th and 19th centuries and submarine warfare in the Battles of the Atlantic during the two world wars. In essence, they used the same tactics to attack and disrupt economic commerce.

Eliminating Piracy
One of the most important maritime reforms of the 19th century was the elimination of “safe harbor” and letters of marque and reprisal.

Europeans recognized they were in a prisoner’s dilemma – two nations would benefit the most if they engaged in free trade, but due to a lack of trust, they funded and supported criminal thugs to attack the other. In the long run, they engage in tit-for-tat piracy that harmed every nation-state.

First, the developing Customary International Law of the Seas defined uniform rules on the high seas to prevent misunderstandings and accidents. This was expanded to include rules regarding privateers. Nation-states used reciprocal rewards and punishments to change the nature of state piracy entirely.

The Declaration of Paris of 1856 explicitly abolished privateering and granting letters of Marque and Reprisal.

But that is just a piece of paper. How was it enforced? Two ways:
1) Use of naval force to punish nations that continued to support piracy.
2) Imperial expansion of power over ungoverned islands and failed states.

Navies enforced the Declaration of Paris by doingg two missions. If a state sponsored piracy or permitted it in its harbors, Navies blockaded the port. They created a ring of wood – surrounding the harbor with frigates and ships of the line, and prevented any ship from leaving the port. Marines would land onshore, inspect the ships, and arrest suspected pirates. Pirates were criminals and illegal combatants – war criminals – and were denied prisoner rights afforded to navy sailors. When captured, pirates were tried by a military tribunal and hanged.

Even the weak United States waged war with the North African Barbary States over their sponsorship of piracy in the first decade of the 1800s. The US Navy and the Two Kingdoms of Sicily blockaded the ports across North Africa, forcing the Muslim Emirs to order their pirates to cease attacks on American and Sicilian ships. Americans and Sicilians no longer had to pay a fee to the Barbary states to prevent pirate attacks.

Not wanting to miss out on a good deal, the British and French engaged the Barbary States as well and, by 1830, forced the North African states to cease state sponsorship of piracy entirely.

Enforcement mechanisms found their way into the Geneva Convention on the High Seas, which required nations to repress pirate activity and punish sponsorship. It included the “right of hot pursuit” into territorial waters. If a navy warship is within sight of a known pirate ship, it is legally permitted to pursue the ship into the territorial waters of another state.

Sponsorship of privateering is now considered an explicit act of war. A state cannot hire pirates to fight a proxy war without repercussions. Rather than swatting at individual flies, nations would attack the sponsor states. This greatly reduced pirate activities in the Caribbean and Mediterranean Seas.

States no longer grant safe harbor to pirates. Modern pirates can only operate out of failed states like Somalia or weak ones like Indonesia. Without sponsorship, they are much weaker than the Privateers in the age of sails.

The legal concept of “Safe Harbor” has important lessons for dealing with non-state actors. State Sponsorship increases the power of pirates, criminals, terrorists, and insurgents by giving them free use of territory, supplies, and advice. If you eliminate the state sponsor, the non-state actors will be reduced in power.