Sean McFate is a senior fellow at the Atlantic Council and author of “The New Rules of War: How America Can Win Against Russia, China, and Other Threats."

In the early morning hours of May 3, a group of armed men tried to land on the shores of Venezuela to topple the country’s leader, Nicolás Maduro. Hours later, they were either dead or captured in a Bay of Pigs-like debacle. Coup attempts in Venezuela are not uncommon, but this one was unique. It was partly led by American mercenaries. Later that day, an ex-Green Beret turned soldier of fortune, Jordan Goudreau, head of Florida-based security firm Silvercorp, took credit for the amphibious raid. Two other Americans were less fortunate and were captured. Maduro gloated over their blue U.S. passports on national television, making his own propaganda coup of events.

The whole operation felt like a bad Xbox game. While it’s easy to laugh and shrug it off, no one should do so. Goudreau may be a farce, but his kind are not. Mercenaries are proliferating at an alarming rate, one of the most significant yet curiously underreported trends in global security. In Yemen, Arab monarchies hired former SEALs and Green Berets to kill Iranian-backed Houthis. In Nigeria, the government employed mercenaries to search for and destroy Boko Haram terrorists, which they did flying in Mi-24 armed helicopters. Moscow hires mercenaries such as the Wagner Group to extend Russian influence in Ukraine, Syria, Libya, Sudan, Central African Republic and Venezuela. They even went muzzle to muzzle with America’s most elite military forces in Syria in a battle that lasted four hours.

Mercenaries sail the high seas in “arsenal ships” and offer “embarked security” for clients traversing dangerous waters. There are cyber-mercenaries called “hack back” companies, who track down hackers and obliterate them. Even terrorists hire mercenaries. In 2016, Malhama Tactical serviced jihadi extremist groups in Syria.

Erik Prince, founder of Blackwater, thinks the United States should outsource its wars; he has claimed a few thousand mercenaries could win Afghanistan. Crazy as it sounds, the plan had supporters. “Why can’t we pay mercenaries to do the work for us?” demanded President Trump of the National Security Council. Prince currently works for China, which the Pentagon considers a strategic competitor. Like all mercenaries, it’s difficult to know where Prince’s true loyalties lie, beyond a paycheck.

Mercenaries are back in ways most people do not know. Often called the “second oldest profession,” they were driven underground by nation-states in the 1850s but started reappearing after the Berlin Wall fell. Every year, their ranks swell and new clients are found. No one knows how many billions of dollars slosh around this market. All we know is that business is booming.

Here’s the problem: Privatization distorts warfare and security in shocking ways, and the world is not ready for it. When conflict becomes commodified, the logic of the marketplace and the strategies of the souk apply to war. In other words, military strategies blend with business ones in ways four-star generals do not comprehend. For example, you can bribe your enemy’s mercenaries to defect and vice versa. Also, mercenaries can sell out their masters. For-profit warriors are not bound by political considerations or patriotism; in fact, this is one of their chief selling points. Their constraint is not the law of war but the law of supply and demand. Historically, we know they start or elongate wars for profit; a world awash in mercenaries means more war.

Mercenaries may be an unstoppable trend because they are difficult to control. Some think we can regulate the market for force, but this is doubtful. Who will go into Syria and arrest all those guns for hire? Not the United Nations or Marines. Also, mercenaries can shoot your law enforcement dead. Others think we should legally go after their clients, but don’t count on it. Consumers are foreign governments, off-shore companies and the mega-rich — all difficult to sue. It may be possible to use market mechanisms to incentivize good behavior, but this requires investing in mercenaries, a dangerous approach.

Where will this lead? Private warriors enable private wars, wresting armed conflict away from the nation-state. This will change everything. When money can buy firepower, then the super-rich will become a new kind of superpower. Oil companies and oligarchs can rent private armies and fight for their interests, the way nation-states do today. Expect wars where nation-states are prizes to be won, rather than drivers of foreign policy. Linking profit motif with lethality will produce grim outcomes for most of humanity.

No one wants the return of private warfare, but few are taking action to slow its growth. Goudreau and his forces may be a joke, but the trend he represents is not: Mercenaries are creeping back into “normal” international relations. The Trump administration has placed a $15 million bounty on Maduro’s head, a highly unusual step that other countries may imitate for their enemies.

Expect more mercenaries, but do not expect them to be Goudreaus.

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