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For nearly a decade, U.S. officials watched with alarm as a shadowy network of Russian mercenaries connected to the Kremlin wreaked havoc in Africa, the Middle East and most recently Ukraine.

A number of them now say they wish the U.S. government had done more.

President Vladimir Putin has increasingly relied on the Wagner Group as a private and unaccountable army that enables Russia to pursue its foreign policy objectives at low cost and without the political backlash that can come from foreign military intervention, U.S. officials and national security experts said.

In recent years, governments in the Middle East and Africa hired the fighters to crush insurgencies, protect natural resources and provide security — committing grave human rights abuses in the process, according to U.S. officials and international watchdogs.

In Syria, Wagner fighters were filmed gleefully beating a Syrian army deserter with a sledgehammer before cutting off his head. In the Central African Republic, United Nations investigators received reports that the mercenaries raped, tortured and murdered civilians. In Libya, Wagner allegedly booby-trapped civilian homes with explosives attached to toilet seats and teddy bears. Last month, German intelligence officials linked Wagner mercenaries to indiscriminate killings in Ukraine.

The U.S. was slow to respond to the danger, and it now finds itself struggling to restrain the use of the mercenaries across the globe, according to interviews with more than 15 current and former diplomatic, military and intelligence officials. Unilateral sanctions have done little to deter the group. Diplomacy has stumbled.

“There was no unified or systematic U.S. policy toward the group,” said Tibor Nagy, who served the State Department for nearly three decades, most recently as the assistant secretary of state for African affairs until 2021.

The Kremlin officially denies any connection with the activities of Russian mercenaries abroad, and much about Wagner’s structure and leadership remains unclear. But experts say that Wagner’s top officers have participated in meetings between foreign leaders and top Russian officials. They also say the Russian air force has transported Wagner fighters to launch the group’s international missions.

Wagner has spread around the world, particularly in Africa, because it presents an enticing package to leaders of embattled nations, experts said. It offers to quash terrorism and rebel threats with brutal military crackdowns, while rallying public support for their government clients through disinformation campaigns.

U.S. officials said they have felt underequipped in trying to curtail the mercenaries’ incursions, in part because American diplomacy in Africa has been gradually stripped of resources over the past three decades. Some also said the U.S. was slow to appreciate the severity of the Wagner threat before it became a formidable weapon in the Kremlin’s arsenal.

In Africa, American efforts to persuade governments not to work with Wagner have generally been late and ineffectual, the officials said. U.S. diplomats have been surprised when Wagner arrives in a faltering country, leaving them scrambling to counter the group’s influence with limited tools and incentives.

During the Cold War, America’s policy of containing the spread of Soviet communism led to a substantial investment in courting African leaders, offering developmental aid, university exchange programs, even concerts. But when the Berlin Wall fell, so too did the U.S. government’s interest in the African continent, the officials told ProPublica. Embassy staffs shrank; programs shriveled.

“America’s soft power is unbeatable, but it needs to be deployed,” Nagy told ProPublica. “The quiver is empty.”

Nagy and other current and former high-level State Department officials said embassies in Africa tend to employ few public diplomacy officers, with barebones staff that must juggle everything from routine visa issues to terrorist threats.

“That doesn’t leave a lot of time for a thin staff to develop the expertise or the relationships necessary to have or pursue a robust engagement strategy,” one senior State Department official said about efforts to steer foreign officials away from Wagner. “The ability of a fairly junior diplomatic officer to build a relationship with the Cabinet member who’s going to be making the decision — that is just not realistic in most cases.”

The State Department declined to comment. The Pentagon and the Kremlin did not respond to questions for this story.

The most visible U.S. effort to keep Wagner out of a specific country transpired in Mali, where the mercenaries arrived last December to fight jihadists rampaging in the north. Malian President Assimi Goïta had recently come to power in the latest of a series of coups that prompted international sanctions.

Before Wagner landed, Gen. Stephen Townsend, the head of the U.S. military’s Africa Command, traveled to Mali to meet with Goïta. “I explained that I thought it was a bad idea to invite Wagner,” Townsend told Congress in March. “Wagner obeys no rules. They won’t follow the direction of the government.”

But the entreaties from Townsend and other U.S. officials were unsuccessful. Former diplomats say the effort was part of a troubling pattern where American officials parachute into complex situations equipped with little more than talking points. Africa Command declined to comment.

The Americans were telling the Malians not to work with the Wagner group but offering no meaningful alternatives, said J. Peter Pham, who served as the first-ever U.S. special envoy to the Sahel region until last year and maintains close contact with Malian and other African officials.

“You either have concrete programs of assistance, or you have personal relationships and diplomatic capital built up over the years that you can call upon,” Pham said. “Many American officials, often of middling rank, are often dispatched with neither.”

In March, the French newspaper Le Monde reported that Wagner mercenaries had participated in the torture of civilians, including by electrocution, while working with Malian soldiers. Last month, Human Rights Watch issued a detailed report accusing Russian fighters of participating in a massacre of roughly 300 civilians during a military operation. The killing began at a crowded cattle market on March 27 and continued for several days. In a statement, State Department spokesman Ned Price said, “We are concerned that many reports suggest that the perpetrators were unaccountable forces from the Kremlin-backed Wagner Group.”

The Malian government has said that the Russians are helping their military as formal instructors, and that their army killed 203 “terrorists” and arrested 51 more during the operation. The Malian Embassy in the U.S. did not respond to requests for comment.

The Wagner group first attracted public notice in 2014, during the Russian invasion of eastern Ukraine. Its mercenaries fought alongside Russian federation forces, attacking Ukrainian forces in the still-contested Donbas region.

Gary Motsek, then a U.S. deputy assistant secretary of defense, was alarmed by the emergence of what seemed to be a new breed of Russian mercenary.

For years, the Pentagon had been aware of Russian military contractors disregarding international law, Motsek said in an interview with ProPublica. But the contractors had mostly been consigned to securing oil tankers and other Russian assets. Now the Wagner Group was in combat, like a private army.

“Looking at the growth of the Wagner Group, it was clearly a missed opportunity” from roughly 2008 to 2010, Motsek said. “We should have made it a priority.”

At the time, Motsek led a Pentagon office that helped create international standards for private military contractors. He said the office focused on voluntary compliance and companies active in American warzones. When the Russians chose not to sign on to the standards, he was not aware of any effort to rein them in.

“It was probably my fault, more than anyone else, because I was the only one working on this on an almost daily basis,” Motsek told ProPublica. “We never went and said, ‘Let’s control these guys.’ I didn’t have the mandate to do that. And I guess I didn’t have the vision.”

American officials say Wagner operates through a web of shell companies controlled by the Russian oligarch Yevgeny Prigozhin, a food industry magnate with close ties to Putin, sardonically referred to as “Putin’s Chef.” Prigozhin has vehemently denied his involvement in the group, supposedly named after the German composer — a favorite of one of the mercenaries’ alleged commanders. Efforts to reach Prigozhin were not successful.

The U.S. sanctioned Prigozhin in 2016 and the Wagner Group in 2017 in response to their role in the Ukrainian conflict. Prigozhin was subsequently indicted for his alleged involvement in meddling with the 2016 U.S. presidential election through the troll farm known as the Internet Research Agency.

Experts say the Wagner Group appears to be paid in proceeds from natural resources like oil, gold and diamonds in countries where they are fighting. The Kremlin has used them as a cheap alternative to Russian armed forces.

“Russia has opened up military operations in two continents, for the first time since the 1980s,” said Sean McFate, a professor at the National Defense University. “The tip of the spear is the Wagner Group.”

In 2015, Russia sent its military to fight in the Syrian civil war on behalf of the dictator Bashar al-Assad. It was the Kremlin’s first armed intervention outside former Soviet territories since the end of the Cold War. Soon, Russian Federation forces and fighters from Wagner and other mercenary groups helped tilt the war in Assad’s favor.

On Feb. 7, 2018, Wagner mercenaries and Syrian soldiers carried out an assault on a U.S. special forces outpost near the town of Khasham, hammering the American position with artillery rounds as the Russians and Syrians advanced. Americans responded with airstrikes in a four-hour battle, killing an estimated 200 combatants. No Americans died.

Joseph Votel, a retired four-star general, was then the head of U.S. Central Command. In an interview, he told ProPublica that he believes the assault was financially motivated, and that Wagner sought control of an oil field near an ongoing U.S.-led counterterror operation.

But Votel said U.S. commanders regarded the fight as an isolated incident rather than a significant development in souring relations between the two nations.

“I didn’t particularly dwell on it,” Votel said. “I wasn’t pressed on it. What happened, happened.”

Joseph Siegle, director of research at the Africa Center for Strategic Studies, said Russian military successes in the Syrian conflict represented an “inflection point for Russia.”

“They saw how quickly they could gain influence in a region where they’d had relatively little influence,” Siegle said.

In 2019, Wagner began to fight in the Libyan civil war, supporting a campaign by the warlord Khalifa Haftar to overthrow the country’s internationally recognized government. Haftar had appeared to be faltering, but, together, Wagner and rebel fighters launched a new offensive that brought their combined forces to the outskirts of Tripoli.

At the top levels of American foreign policy agencies, alarm bells were beginning to sound.

“We were watching it change the course of the war,” David Schenker, then assistant secretary of state for Near Eastern affairs, said in an interview with ProPublica. “This was the beachhead. Wagner was the landing party.” Haftar’s attempt to retake Tripoli ultimately stalled after Turkey intervened on the opposing side. But if Haftar had succeeded, Schenker worried, Russia could have been rewarded with “a base on NATO’s southern flank.”

Schenker said he believed the most immediate potential countermeasure was to push the European Union to impose sanctions on Wagner and crack down on its finances. But he said many of his colleagues in the U.S. government and in Europe didn’t view that as realistic.

“I really pressed hard for a designation from the E.U. What’s complicated is that Russia routinely goes and assassinates dissidents in foreign countries,” he said. “People weren’t interested in angering Putin. Putin for these guys is like Voldemort.”

The E.U. did not impose sanctions on Wagner until December 2021.

In response to questions for this story, E.U. spokesperson Nabila Massrali said the E.U. aggressively sanctioned Russia in response to the invasion of Ukraine and sanctioned Wagner “to take tangible action against those threatening international peace and security and breaching international law,” noting that all sanctions require unanimity among member countries.

As the Ukrainian conflict drags on and the Kremlin becomes further isolated from the global economy, experts say that Wagner is likely to play an increasingly important role in Russian foreign policy. The Wagner Group’s expansion could help Russia evade the impact of sanctions, entice governments to support it in the U.N. General Assembly and secure strategic positions in its fight against the NATO alliance.

Economically, Russia pales in comparison to superpowers like China and the United States. But in the Wagner group, officials said, Russia has found a cheap and novel foreign policy tool that America has yet to find a way to address. Client governments appear to absorb most of the cost.

“The Russians don’t have a blank checkbook,” said Nagy, the former top U.S. diplomat for Africa. “They are playing a fairly weak hand extremely, extremely well.”

ProPublica will continue to report on the Wagner group and the power struggle between the U.S. and Russia as it plays out around the globe. We are especially interested in relationships between Western companies and Russian mercenaries.

If you know about these issues, please contact reporters Joaquin Sapien at joaquin.sapien@propublica.org or Joshua Kaplan at joshua.kaplan@propublica.org. We take your privacy seriously and will contact you if we wish to publish any part of your story.