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What Does Arming an Insurgency in Ukraine Mean?

Vladimir Rauta, Alexandra Stark
Sunday, April 3, 2022, 10:01 AM

Research on insurgencies holds lessons for how to aid Ukraine, but assessing what policies are best will depend on how the conflict proceeds.

Ukrainian troops practice urban operations on Sept. 22, 2021, during the Rapid Trident 2021 joint exercise near Lviv, Ukraine. Photo credit: SSG David Carnahan/Public Domain via DVIDS.

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Editor’s Note: As the United States and its European allies funnel military aid to Ukraine, the conflict has taken on at least some dimensions of a proxy war—a subject Lawfare has addressed repeatedly. Vladimir Rauta of the University of Reading and Alexandra Stark of New America dissect this perspective, examining which aspects of the existing analysis on proxy war apply to Ukraine and, perhaps more importantly, which do not.

Daniel Byman


Proxy wars proved a popular tool for U.S. and Soviet policymakers throughout the Cold War to compete for global influence while avoiding a direct confrontation between the two nuclear-armed powers—to the detriment of the millions of people who were killed in or otherwise harmed by these wars. Yet the strategic appeal of arming proxies did not fade with memories of the Cold War, and the problems they pose remain acute. From debates within the Clinton administration on whether or not to arm the Kosovo Liberation Army, to successive administrations working in tandem with proxies disguised as partners in Afghanistan and Iraq, to President Obama’s hesitation to support Syrian rebels against the regime of Bashar al-Assad and his later embrace of Kurdish militias fighting the Islamic State, arming proxies remains a popular policy tool in response to armed conflict. 

As events have unfolded in Ukraine, several prominent voices have advanced the idea of arming an insurgency in Ukraine. Few of these proposals, though, examine the question of what it would mean to support a Ukrainian insurgency. The asymmetry of power between Russia and Ukraine, the fact that Ukrainians are already practicing irregular warfare, reporting that indicates the CIA has been overseeing a training program for elite Ukrainian special operations forces, and a history of successful anti-Soviet resistance shape the prospects of a potential insurgency. 

The conversation about arming a Ukrainian insurgency has tended to muddle concepts, including the distinctions between intrastate and interstate wars, and between providing security assistance to governments versus sponsorship of rebels. These may sound like pedantic academic distinctions, but they carry a lot of meaning for policymakers: Supporting and arming a sovereign government is conceptually and practically different from arming an insurgency, in terms of international norms as well as how that support proceeds in practice. Characterizing U.S., British, or NATO and European Union countries’ military assistance to Ukraine as “funneling weapons to kill Russians” obfuscates how this aid is authorized and supported by national legislation and provides poor comparative benchmarks with previous instances of covert and deniable sponsorship of armed non-state actors as proxies.    

The debate regarding arming a hypothetical insurgency in Ukraine would benefit from clear definitions. The academic literature, and for that matter international law, draws a conceptual distinction between interstate and intrastate wars. But the literature also demonstrates that these concepts sometimes overlap and that intrastate wars don’t occur in a vacuum; it is helpful to think about “civil war as international politics by other means.” Russia’s war in Ukraine is both an interstate war between two governments, Russia and Ukraine, and an intrastate war between the Ukrainian government and Russia-supported separatists in the breakaway regions of Luhansk and Donetsk. And because the war sits at the intersection of these two types of conflict, it has met the definitional requirements and thresholds of an internationalized civil war, namely a conflict in which at least one of the parties is supported with troops from an external state. This means that findings about interstate or intrastate wars—how intervention affects the dynamics or duration of a war, for example, or the sustainability of peace afterward—don’t necessarily apply.

Neither of us knows how Russia’s war in Ukraine will end, or even where it is most likely to go next. Looking at the predictions made by experts on Russia and military operations, however, there are two broad scenarios that would conceptually change the debate about providing material support to Ukrainian forces. Academic research suggests there are important, policy-relevant differences between whether Ukraine is occupied and insurgents wage a civil war against a Russia-imposed government or conflict continues in contested spaces against the backdrop of a tense cease-fire or stalemate.


Scenario I: Civil War


In the first type of scenario, Russia is able to overcome its initial military setbacks enough to send the democratically elected Ukrainian government into exile and attempt to occupy the country and/or install a puppet regime, a contingency for which Western officials are reportedly already planning. Avril Haines, the director of national intelligence, has said that if the Zelenskyy government falls and a Ukrainian resistance continues to fight the new Russia-backed government, there “is likely to be a persistent and significant insurgency.” As such, the conflict would become a civil war. This is the set of potential scenarios in which it would make sense to talk about arming an insurgency—and in which insights from the literature on civil war would be relevant. 

Arming an insurgency is associated with negative outcomes: wars that are longer, deadlier and more brutal to civilians. Often discussed as a cost-benefit transaction, support for proxies is neither cheap nor risk-free. The costs of supporting the mujahideen in Afghanistan were astronomical, and Obama’s train-and-equip program to support Arab opposition forces in Syria came with a $500 million price tag (and not much to show, either). Indeed, while funding rebels has been shown to be a more fungible form of support compared to others—for example, sanctuary is very common but increases the probability of international conflict—costs come in different forms, thereby making proxy wars more complex and unpredictable in terms of their effects. Specifically, while sponsors substitute the costs of engaging in war directly—saving manpower and some money—they run the risk of retaliation. This retaliation can occur through in-kind support to a rival party, producing a mutual or competitive intervention in which both sides fighting a civil war receive external backing and prolong the conflict; it can also occur as direct punishment targeting the sponsor, given that external support risks initiation of interstate conflicts. For this reason, supporting insurgents in this scenario is an extraordinarily difficult policy choice. Effective support for an insurgency might provoke Kremlin attacks on neighboring countries that provide support and/or safe havens.  

The choice of providing support would rest largely on the questions of who the insurgents were and what they could feasibly achieve. The goals of external supporters matter, but they also change. Civil wars are likely to last longer when the aims of sponsors are misaligned with the goals of proxies, but not necessarily when sponsor and proxy goals are more closely aligned. There are important context-specific distinctions between a potential future Ukrainian insurgency and other recent conflicts in which the United States has supported proxy actors, like the Syrian civil war. In fact, partisan warfare and efforts to arm and train local resistance forces during World War II might be a more useful analogy than support for the Syrian opposition. A Ukrainian insurgency against a Russia-backed government would, in all likelihood, have close ties to the democratically elected government, which is important, given new insights into the relevance of rebel leaders’ political backgrounds for their effectiveness in obtaining support. The insurgency in this scenario would also command a great deal of legitimacy and would be capable of unifying opposition on the ground. An insurgency’s being framed as a people’s war against inefficient and insufficient forces of Russian invaders could act as a buffer against fragmentation and invite a reconsideration of assessments of the relationship between external support and postconflict democratization trajectories and disarmament, demobilization and reintegration (DDR) processes


Scenario II: Interstate and Intrastate War


The second set of scenarios, which some observers see as more likely due to Russia’s underwhelming military performance so far, would involve some kind of long-term cease-fire or settlement between Ukraine and Russia by which Russia retains its territorial acquisitions and the Zelenskyy government continues to govern the rest of the country. Here, the likely result would be an interstate war (whether frozen or active) in parallel with potential insurgencies in Russia-controlled territories that are closer to internationalized civil wars. Most likely, external actors would continue to provide support for the Ukrainian government but would face a more difficult decision regarding arming Ukrainian insurgents in contested territories. Russia, though, would be likely to continue supporting forces in Ukrainian territory and deploying mercenaries like the Wagner Group.

Arming an insurgency in this case would parallel the efforts of the Ukrainian armed forces. Proxy fighting could follow pockets of resistance that map onto the militias that fought on the side of the government in early 2014-2016 and later either disbanded or integrated into the Ukrainian armed forces—the Azov Battalion, the Right Sector or the privately financed Donbass Battalion. The origins of such battalions and their political preferences might pose similar problems for vetting as was the case with selecting Syrian rebels into U.S. train-and-equip programs; these challenges could be compounded further by the fact that sometimes military assistance pushes rebels to fight in inconsistent locations as well as each other, and could be exacerbated by a potential influx of foreign fighters. Moreover, recent research has shown how these battalions followed self-serving strategies, speaking to classic problems in conflict delegation: proxy liability and unreliability. Within this scenario, and to a certain extent the previous one too, fragmentation could undermine the insurgent effort, especially given that external resources can promote either rebel cohesion or splintering depending on how funds are allocated among rebel elites, while contributing to the prospect of war recurrence.

It is difficult to come up with a close historical analogy for this scenario. The decline of interstate war means there are fewer recent cases to draw on, especially cases in which one side is armed with nuclear weapons or backed by a nuclear-armed state, or where at least one side is arming insurgents within their opponent’s borders. (The Iran-Iraq War, Sudan-South Sudan War and Ethiopian-Eritrean War all come to mind here, but they lack the risk of nuclear escalation.) There is just not as much to go on when trying to understand what arming insurgents would look like, or the potential effects on escalation dynamics. One avenue would be to turn to research into pro-governmental militias and variation in types of sponsorship relationships as they sit on an even wider spectrum of internal conflict delegation. Once again, the record stacks against the policy: Proxies become spoilers of peace,  play into repertoires of illicit state violence and negatively affect postconflict settings.




The idea of arming a Ukrainian insurgency raises more questions than it answers. What arming an insurgency could mean for the duration of the conflict, for the well-being of civilians, and for the battlefield success of an insurgency depends a great deal on context. During an international crisis, it is not enough to “do something” by reaching for the same simple policy solutions—advocates also need to understand exactly what it is they are proposing and what the implications could be.

Vladimir Rauta is a lecturer in politics and international relations at the University of Reading. He holds a doctorate from the University of Nottingham and was previously a fellow at the Middle East Studies Forum at Deakin University’s Alfred Deakin Institute for Citizenship and Globalization.
Alexandra Stark is an associate policy researcher at the nonprofit, nonpartisan RAND Corporation.

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