The Risky Status of Ukraine’s Foreign Fighters

Russia has labeled Ukraine’s foreign fighters “mercenaries”—raising questions about their legal status if captured.

By , an associate professor of public affairs at American University.
Two men wearing backpacks jointly carry a large duffel bag as they walk away from the camera toward a building.
Two men wearing backpacks jointly carry a large duffel bag as they walk away from the camera toward a building.
Two men who said they were from London walk toward Poland’s Medyka border crossing with Ukraine on March 11 to join the fight against Russia. Sean Gallup/Getty Images

On Feb. 27, Ukrainian President Volodymyr Zelensky announced the formation of a foreign legion, called the International Legion for the Territorial Defense of Ukraine, that incorporates the foreign volunteers who had already come to Ukraine to fight Russia and aims to recruit others via a tourism website. Ten days later, Ukraine reported that it had received 20,000 requests to join from people in 52 countries. U.S. citizens were among the first new enlistees.

But what will happen to those foreign volunteers when some are inevitably captured or killed? If Ukraine is enlisting foreign volunteers into its regular military, something it also did in the 2010s with the foreigners who joined nationalist militias to fight pro-Russian separatists, then they should have full rights as soldiers under the Geneva Conventions.

Under international law, when soldiers become noncombatants when wounded or captured, they are supposed to be protected from reprisals, torture, or degrading treatment as hostages, and they must be provided legal protections against collective punishment for acts of their country. However, mercenaries do not enjoy the same protections as lawful combatants, including the rights afforded to prisoners of war, and governments are free to treat them as they see fit.

On Feb. 27, Ukrainian President Volodymyr Zelensky announced the formation of a foreign legion, called the International Legion for the Territorial Defense of Ukraine, that incorporates the foreign volunteers who had already come to Ukraine to fight Russia and aims to recruit others via a tourism website. Ten days later, Ukraine reported that it had received 20,000 requests to join from people in 52 countries. U.S. citizens were among the first new enlistees.

But what will happen to those foreign volunteers when some are inevitably captured or killed? If Ukraine is enlisting foreign volunteers into its regular military, something it also did in the 2010s with the foreigners who joined nationalist militias to fight pro-Russian separatists, then they should have full rights as soldiers under the Geneva Conventions.

Under international law, when soldiers become noncombatants when wounded or captured, they are supposed to be protected from reprisals, torture, or degrading treatment as hostages, and they must be provided legal protections against collective punishment for acts of their country. However, mercenaries do not enjoy the same protections as lawful combatants, including the rights afforded to prisoners of war, and governments are free to treat them as they see fit.

The standards for identifying mercenaries are also arbitrary. Under international law, they are foreign participants in the conflict who are motivated primarily by personal gain. That motivation is difficult to prove or disprove for anyone. And there are in fact some soldiers for hire among the number of legionnaires who have traveled to Ukraine, blurring the distinction. Moscow even appears to be importing its own mercenaries from Syria. But Russia can claim it is following international law in any actions it might take against foreign legionnaires if they are not regarded as legitimate soldiers.

Indeed, it took just four days for Russia to declare that it would not treat foreign volunteers fighting for Ukraine as lawful combatants, raising uncomfortable questions not only about the risks facing the volunteers but the potential greater risk that their home countries will be drawn more directly into the conflict as well.


On March 3, the Russian Defense Ministry referred to all foreign volunteers in Ukraine as “mercenaries,” none of whom “can be considered as combatants in accordance with international humanitarian law or enjoy the status of prisoners of war… At best they can expect to be prosecuted as criminals.” In the context of the Russian approach to other foreign volunteers, the policy is even worse for any captured combatants than it sounds.

During the war in Chechnya, Russia announced that any foreigner suspected of being on the side of terrorists would be killed on sight, which is what happened in 2004 to one Canadian filmmaker whom Moscow claimed was really training rebels in how to use explosives. In the Soviet era, the Kremlin described foreign fighters as “bandits” and had them tried on the spot in “people’s tribunals” rather than by the regular courts.

Russia has already acted on its threats with the aggressive step of a missile strike on a military facility near Ukraine’s border with Poland on March 13, on the grounds that it was “a training facility for Western mercenaries.” If no foreign volunteers were killed, it was not due to restraint.

If history is any guide, this policy could lead to significant unintended consequences, because accompanying the question of the legal status of foreign combatants is the question of how the governments and publics of their home countries will react to executions or other mistreatment of their citizens.

This is evident throughout modern history in cases of foreign fighters, which security analysts define differently than foreign legionnaires because the former fight with rebels and militias rather than joining recognized national militaries. Most definitions of foreign fighters distinguish them from mercenaries because they are not employed by states and are often clearly not in it for the money, such as jihadi suicide bombers for the Islamic State.

Technically, the volunteers fighting alongside pro-Russian separatists in Donbas are the only ones in Ukraine who would count as foreign fighters in this conflict. Still, the harsh treatment that foreign fighters typically receive and the backlash that this can create provides a valuable lesson that how Russia treats captured foreigners on a Ukrainian battlefield or city street might only increase the resolve of its adversaries and perhaps provoke them to war.

Foreign fighters have been a feature of conflicts for centuries. One instance the Russian policy in Ukraine echoes is that of Mexico in 1836 when it faced an independence movement in Texas bolstered by roughly 2,000 foreign volunteers. Like Russian President Vladimir Putin today, Mexican President Antonio López de Santa Anna at the time dismissed his adversaries as unlawful and therefore decreed summary executions for any foreigners.

He claimed that “all the existing laws, whose strict observance the government had just recommended, marked them as pirates and outlaws.” But his mass executions of European and American prisoners after battles like the Alamo swung public support in the United States and elsewhere in favor of Texas independence to escape such brutality. And they produced new waves of volunteers seeking vengeance who succeeded in ending Mexican rule in Texas.

More recently, it was the United States that employed the term “unlawful enemy combatant” against its adversaries, starting with Afghanistan in 2001. Like the Russian response in Chechnya, the United States also did not seek prosecutions of detained suspected al Qaeda operatives through the normal criminal justice system. Instead, it declared that because the foreigners were not part of a national military, they were not soldiers and therefore had no rights as prisoners of war. The solution was to send them, in some cases indefinitely, for interrogation and torture at the U.S. detention facility at Guantanamo Bay in Cuba.

This policy undermined international public support for the U.S. war on terror. And the treatment of prisoners at Guantanamo, and later at Abu Ghraib in Iraq, appeared in jihadi propaganda recruiting more foreign fighters to Afghanistan and Iraq to fight against American occupation in the name of saving Muslims from such treatment. Arguably, the expedient of depriving foreign fighters of any rights undermined U.S. efforts in Afghanistan and contributed to its defeat.

Russia has not provided any indication that it is concerned about such a backlash from its actions in Ukraine. Few other governments have either. A handful, including Algeria and Senegal, have prohibited their citizens from going to Ukraine by arguing that international law does not permit it. The United States and most others have issued statements from skepticism and suggestions the citizens perform aid work instead to full-throated endorsements of foreign volunteers fighting against Russia.

They have not, however, addressed what if anything they would do to secure the release of their citizens if they are captured or facing execution. Imagine this happening to American, Japanese, Indian, or British fighters, nationalities all reportedly on the ground already. Public outrage might not push those governments into open war with Russia, but it might make deescalation or negotiated settlements more difficult to support.

To minimize this risk, governments need to announce policies on foreign volunteers now. They could choose to disavow their own citizens. However, the possibility of a video showing the torture or execution of a foreign volunteer going viral cannot be discounted. This would similarly produce a drumbeat for action to avenge national martyrs and protect other volunteers that would be difficult to ignore.

Instead, just as most governments in the world recognize Ukraine’s claim to sovereignty, they must also reiterate now that they will recognize the legal standing of all enlisted members of Ukraine’s military as lawful combatants. This may be the only way to protect the rights of their citizens and their national interests, even when their own citizens have opted to put Ukraine’s national interests ahead of their own.

 

David Malet is an associate professor of public affairs at American University. He is the author of the book Foreign Fighters: Transnational Identity in Civil Conflicts. Twitter: @drdavidmalet

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