The two best-known private armies in modern times are America's "Blackwater" and Russia's "Wagner Group". While both prefer to employ former special forces operatives, the high demand for their profitable services means they have sometimes employed poorly disciplined "cowboy" elements.
(A private army is defined as a military or paramilitary force consisting of armed combatants who owe their allegiance to a private person, group, or organisation - rather than to a nation or state.)
The American force's website currently says "Now recruiting former law enforcement officers, corrections officers, security guards and military personnel to join our team overseas." The force is believed to have about 22,000 employees, including Australians.
Former US Navy SEAL officer Erik Prince founded Blackwater in 1996. Its first major contracts were to provide the US with security services in Afghanistan and Iraq.
In 2007, it became notorious for the Nisour Square massacre in Baghdad, when Blackwater security guards killed 17 unarmed Iraqi civilians and wounded 20. In 2014, four of its operatives were tried in the US and found guilty of opening fire on a crowd of civilians while escorting a diplomatic convoy. One was given a life sentence while the other three were given 30-year prison terms. In December 2020, president Donald Trump pardoned them and they were released.
Blackwater was renamed "Xe Services" in 2009 and, after it was acquired by a group of private investors, renamed "Academi" in 2011.
The organisation tries to avoid publicity but occasionally receives unwanted attention. In 2015, six of Academi's Colombian mercenaries were reported killed in Yemen. The mercenaries were led by an Australian commander who was also killed. They were part of a battalion of foreign troops hired by the UAE to fight against the Houthi insurgency. News services identified the dead Australian as Philip Stitman, about whom little is known publicly.
in 2014, Academi merged with "Triple Canopy", a subsidiary of Constellis Holdings Incorporated, and in 2015 began operating as "Constellis". (In September 2016, Constellis was bought by Apollo, an American asset management company, but continues to operate as Constellis.)
In 2016, Iranian Farsnews claimed that over 300 mercenaries from Blackwater had been killed in Tochka missile strikes in Yemen, including their commander US Colonel Nicolas Petras. This was not confirmed from other sources.
Constellis' advertising says it's "a company providing risk management, security, humanitarian, training, and operational support services. It offers background investigations, social intelligence tools, advanced training, logistics, life support, crisis response mitigation, and unmanned aerial vehicle and police dog services."
Constellis' main income seems to come from providing contract security services to the US federal government, including the CIA and US State Department.
While Constellis is a recognised legal entity with its own extensive training facilities in the US, the Russian Wagner Group operates "illegally" in Russia because private military contractors are banned from operating there.
Russian oligarch Yevgeny Prigozhin, a businessman with close links to President Putin, founded the Wagner Group in 2014. It first came to global notice in 2014 with its involvement in the fighting in Donbas, Ukraine, where it supported separatist forces of the self-declared Donetsk and Luhansk People's Republics.
Since then, its operatives have been involved in conflicts in the Middle East and Africa - including the civil wars in Syria, Libya, the Central African Republic, and Mali, often fighting on the side of forces aligned with the Russian government. Wagner Group operatives have allegedly committed war crimes in areas where they are deployed, including killings, rapes and robberies of civilians, and torturing deserters.
Because the Wagner Group operates in support of Russian interests, it receives military equipment from the Russian Ministry of Defence and uses Russian defence installations for training purposes.
It's therefore believed to be used as an "unofficial" unit of the Ministry of Defence and a tool of Russia's military intelligence agency, the GRU.
Use of the Wagner Group allows the Russian government to "plausibly deny" official involvement in external conflicts and hide from the Russian public the number of casualties and financial costs of Russia's external interventions.
In Ukraine, since late 2022 the Wagner Group has been heavily involved in Russian efforts to capture the city of Bakhmut, in eastern Ukraine.
In December 2022, White House spokesman John Kirby told reporters that "in certain places, Russian forces are subordinate to Wagner's command." He claimed, "Wagner has an estimated 50,000 personnel inside Ukraine ... that includes 10,000 contractors and 40,000 convicts recruited from prisons."
Recent reports suggest that President Putin is trying to rein in Prigozhin's growing political influence, while the Ministry of Defence has been reluctant to acknowledge that Prigozhin or the Wagner Group is responsible for any of its recent battlefield successes in Ukraine.
Private armies can be a useful state instrument because of their deniability and relatively low cost compared to regular armed forces.
On the down side, they can be difficult to control and can become a rogue military element that threatens the state.
Putin will be well aware of the precedent of the French OAS, a far-right French dissident paramilitary organisation that tried to kill French president de Gaulle in 1962 because its members disagreed with de Gaulle's Algeria policy.
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