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The Russian Military Buildup on Ukraine's Border | An Expert Analysis

Over the past few weeks, Russia has amassed a large number of troops and military assets in Crimea and at the Ukrainian border.

The Kennan Institute recently asked several of our experts and friends to weigh in on this developing story and consider the following questions:

1.    What is behind the ongoing military buildup by Russia on Ukraine’s eastern border and in Crimea? 

2.    Is this a show of force, a presage to military confrontation or invasion of Ukraine by Russia, or something else?

3.    If Russia does undertake offensive operations in Ukraine, what might that look like and how might the U.S., Europe, and NATO respond?

Read analysis from Victor Andrusiv, Oksana Antonenko, Mykhailo Minakov, Igor Zevelv, and Brig. Gen. (ret) Peter Zwack below!

Explore the Analysis from Our Experts




    Two factors are driving Russia’s recent aggressive behavior. The first is the water crisis in Crimea. The situation is difficult—people currently receive water for only a few hours per day—and it has the potential to get worse. The Russians are under pressure to act to solve this issue. As far as I know, the head of Ukraine’s presidential administration, Andriy Yermak, promised to supply water to Crimea in spite of the Russian occupation. Now, however, the Russians believe that Yermak and President Volodymyr Zelensky have cheated them by reneging on this deal. The second factor is the Biden administration’s prospective strategy for Russia. President Joe Biden’s comments calling President Vladimir Putin a “killer” were a sign that the new U.S. administration is in favor of a stricter approach than its predecessor. The goal of Russian aggression on Ukraine’s border is to bring Biden to take a more peaceful approach, as Putin believes that the United States is not prepared for a new conflict in Ukraine. The recent call between both leaders is a sign that Putin was right.

    All that said, the Russians may also be considering a military invasion into Ukraine. The show of force on Ukraine’s border could turn into a real war. I believe, however, that as soon as Russia secures water or gets Biden to the table, the Kremlin will begin deescalation. If war were to break out, I do not think it would result in a deep invasion into Ukraine. The Russians will focus on destroying Ukraine’s military forces in order to threaten Ukraine into signing lopsided agreements. The Russians might also try to capture the Crimean channel, which supplies the peninsula’s water and is located only 80 kilometers from the peninsula.

    In the event of war, I expect the reaction from the United States and European Union to be very weak and focused on quickly achieving peace. So if, for instance, the Russians can capture the Crimean channel and threaten to move on Odessa, but actually stop at the channel, it will be treated as a victory of diplomacy. That said, a strong U.S. or EU response, including sanctions or military support to Ukraine, might be viewed as provocation leading to further escalation.

    My recommendation to the United States and European Union would be to put in place concrete steps that will send a strong message to the Russians that they may not win a fight in Ukraine. First, the United States or NATO should amass weapons outside of Ukraine’s border, such as in nearby Poland. These weapons could be transferred to Ukrainian soldiers in the event of a Russian invasion. Second, the United States and European Union should prepare to institute oil and gas embargoes on Russia. Both of these steps would force the Russians reconsider or change their behavior. However, they will have to act quickly as the Russians are in position to swiftly transition into military operations.

  • The recent buildup of Russian forces near the border with Ukraine and in Crimea and the escalation of fighting along the cease-fire line in Donbas offer a clear illustration of the current precarious fragility of the European security order. In a matter of days, the situation shifted from a relative stability to a credible (though still unlikely) threat of an all-out interstate military conflict.

    The current crisis is dangerous because its exact triggers, purpose, and objectives are more ambiguous than ever before. Each side’s red lines remain badly understood or even are deliberately left out of formal negotiations. There are reasons to believe that Russia’s motives are primarily political rather than military. The Kremlin is trying to reframe the terms of Russia-West relations by moving Moscow from the position of an object of U.S. and European sanctions (over election interference and the poisoning of dissident Alexei Navalny) to the subject of the most important discussions related to the European security agenda.

    Once again, this tactic—previously tested in Syria—seems to have delivered results. After several months of alienation from the West, Vladimir Putin has placed himself at the center of diplomatic activity, including the prospect of the first U.S.-Russia summit in several years. Moreover, this escalation also has helped to mobilize nationalist sentiment within Russia just as the State Duma election campaign is due to start in April, following Putin’s much-anticipated annual address (which some commentators are already comparing with his 2007 Munich speech).

    However, as in the past, the strategy behind this gamble is highly problematic. The absence of trust and functioning deterrence (and confidence-building) mechanisms mean that the growing concentration of forces could be used by the “party of war” to provoke a real conflict. Many forces on both sides—in Russia (and its proxies) and in Ukraine—are eager to upgrade their status and financial position as a result of a new instability. But even as the crisis has illuminated Russian military superiority, it also has highlighted its economic weakness. The Russian ruble has depreciated sharply, and the real incomes of ordinary Russians will continue to decline amid accelerating inflation and rising unemployment. Unlike the previous U.S. administration, President Joe Biden has been pursuing parallel courses of sanctions and diplomacy, which will continue to expose the Kremlin’s vulnerability. Putin will likely find it more difficult to show to the Russian people, and in particular its economic and political elite, that his gambling tactics are paying off. Yet there is no reason to believe that he will abandon this aggressive diplomacy in the future.

    The introduction of new, tough U.S. sanctions shortly after the first Biden-Putin phone call has sent a clear signal to Moscow that the U.S. side sees only very limited space for dialogue – it will not prioritise trust-building and will continue to rely on deterrence via sanctions and greater commitment to its European allies – as the main vehicle for constraining Russian foreign policy ambitions. The success of this approach, which has not been tried since the Reagan era, remains uncertain. Unlike Gorbachev, Putin sees no reason to seek a compromise with the “declining” (in his world view) West and he will continue to pursue closer alliance with China to counter U.S. pressure. 

    What does it mean for the current Russia-Ukraine crisis? Existing deescalation mechanisms, such as arms control regimes (Vienna Document) or various dialogue formats (from OSCE to the NATO-Russia Council), offer no effective ways to mitigate risks. This is an extremely dangerous reality not merely for Ukraine but for central and eastern Europe as a whole. Building or rebuilding such deescalation mechanisms should be at the top of the priority list for the future U.S.-Russia—and, more broadly, Russian-Western—discussions.


    The recent Russian military buildup on the western borders of Russia and in the annexed Crimea, as well as a media campaign to mobilize support in Russian populations for a possible military action in Ukraine, were indeed menacing. The Ukrainian government responded with its own defense, diplomatic, and mass media preparations for a possible attack. In the months since the end of January 2021, the hope for a more diplomatic solution—which was palpable in the fall of last year—has evaporated and the general sentiment has shifted toward an anticipation of war.

    The escalation in Ukraine-Russia tensions has at least two dimensions. First, it is connected with the shift in relations between Kyiv and Moscow since the end of 2020. Yet another failure to find common ground on the implementation of Minsk agreements has opened a new opportunity for those who want a military solution to the conflict, as well as those who would rather restart the diplomatic process under new conditions. By April 13, when the escalation reached dangerous levels of publicly expressed hostility between Moscow and Kyiv, the relations of the two governments had radically changed. Kremlin demonstrated its unwillingness to continue political dialogue with the Ukrainian leadership. The Kremlin-backed separatists declared new goals: turn their statelets into “new Russian national states” that—if Ukraine were to attempt to retake them by force—would be defended by Russia and gain Russia’s recognition, as in the case of Abkhazia in 2008. In Ukraine, political forces with pro-Russian orientations were sanctioned and their influence was limited. Officials in Kyiv have returned to the policy of linking the Donbas issue with the Crimean one, and are preparing for an international diplomatic congress on Crimea. Now, if and when new talks on regional issues start, any Ukraine-Russia dialogue will be taking place in a new setup.

    The second dimension behind the current escalation is connected with the worsening relations among Russia, the United States, and the European Union. After the European Union’s humiliation in the Borrell incident and President Joe Biden’s inflammatory statement about Vladimir Putin, it was only a matter of time before the Kremlin began to escalate tensions in Ukraine. Following the U.S. and Russian presidents’ phone conversation on April 13, some deescalation is possible. However, taking into account the U.S. sanctions as of April 15 and the upcoming reaction of Kremlin, the risks of active military operations on the Donbas frontline remain high. Also, Russia may opt to use the issue of water for Crimea as some sort of casus belli for an invasion of southern Ukraine. However, any longer-term solutions will depend on the results of the meeting between the U.S. and Russian leaders.

    If, in the end, war—or more precise a “limited military incursion”—does happen to break out, taking into account the seven-year-long experience of military conflict in the region and the different forms of the Western involvement, Ukraine would need immediate, equally intensified diplomatic and military support from the United States, the European Union, and NATO. This support would need to aim at deescalation, countering aggression, and nonproliferation of the military actions into other Ukrainian territories.

  • The conflict in eastern Ukraine, never properly frozen, could have become a full-scale regional war in March-April 2021—and yet it did not. The tensions in the region began to deescalate after President Joe Biden spoke with President Vladimir Putin on April 13. A future summit meeting may give peace a chance if the conflict resolution is put into a broader context of U.S.-Russia engagement. Without normalization of relations between the two countries, the prospects for peace in Ukraine are dim.

    Moscow conceptualizes and narrates the conflict not as a Russian-Ukrainian issue, but as a clash between Russia and the West on the territory of the Russian world. The Ukrainian people—who, Putin believes, are one with the Russian people—are therefore not a party to the conflict. The Kremlin regarded the 2014 revolution in Kyiv as a coup d’état organized by the West on the Russian world’s ground. In Putin’s words, “with Ukraine, our Western partners have crossed the line. . . . Russia found itself in a position from which it could not retreat. If you compress the spring all the way to its limit, it will snap back hard.” Western policies toward Eurasia in the more than three decades since the collapse of the Soviet Union have only strengthened Russian anxieties. Moscow is confident that the main goal of the United States and Europe in Eurasia is the containment of Russia. These Western policies are seen as an attempt to deny Russia its historic mission and a role as a “natural” regional hegemonic power.

    In the spring of 2021, Russia stationed the highest number of troops along Ukraine’s border since 2014. Russia’s defense minister said that the country’s massive military buildup was part of readiness drills amid what he described as threats from NATO. Indeed, one of the largest U.S. Army-led military exercises in Europe in decades kicked off in March and will run until June, with 28,000 total troops from 27 nations taking part in it. The “Defender Europe 2021” exercise will include “nearly simultaneous operations across more than 30 training areas” in a dozen countries.” In spite of the dangerous military buildup on both sides, the U.S. intelligence community’s Annual Threat Assessment, issued only four days before Biden’s conversation with Putin, said that “Russia does not want a direct conflict with US forces… Russia seeks an accommodation with the United States on mutual noninterference in both countries’ domestic affairs and US recognition of Russia’s claimed sphere of influence over much of the former Soviet Union.”

    The United States, Russia, and Ukraine could find a way to present the emerging chance for deescalation as a win-win-win situation for all parties concerned. Washington may say that “America is back”—President Biden voiced concerns over the sudden Russian military buildup in occupied Crimea and on Ukraine’s borders, called on Russia to deescalate tensions, and thereby prevented the outbreak of war. Moscow, in turn, may say that Biden’s proposal of a summit meeting with Putin in the coming months proves that the Russian show of military force and clear demonstration of will were enough to force America to recognize Russia’s role in the world. Kyiv, for its part, may say that the United States and NATO offered support to Ukraine in its conflict with Russia and stood firmly behind its sovereignty and territorial integrity. Both Russia and Ukraine got what they wanted from the United States. The United States got what it wanted most: a renewed image of itself as a global leader. Meanwhile, around 14,000 people have died in the war, and prospects for conflict resolution remain unclear at best.

  • For the ongoing Russia-Ukraine conflict, pressure has been building up at several levels over recent years. At the macro level, Russia’s relations with the United States (and, by extension, NATO) have deteriorated significantly as a result of the continuous flow of Russian disruptive and adversarial actions since its invasion of Ukraine in 2014. These actions include the U.S. presidential election hacks of 2016 that especially polarized the U.S. democratic landscape regarding Russia; Russian actions in Syria; the undermining of European institutions; the poisoning of Sergei and Yulia Skripal in the United Kingdom; the poisoning, arrest, and incarceration of dissident Alexei Navalny; the SolarWinds hack; and reports of specific meddling in the 2020 election against presidential candidate Joe Biden. In aggregate, it has led to the current round of sanctions against Russia. All of this is only the backdrop to the festering relationship between Kyiv and Moscow that has drawn in the United States/NATO and the European Union (EU), making the region all the more fraught and tense—especially with firmly declared, material U.S./NATO and EU support for Ukraine’s sovereignty and territorial integrity. Russia’s aggressive behavior regionally and worldwide seemingly masks its deep, embedded fears of threats along its extended 11-timezone periphery and an anxiousness that its population, while patriotic, is also restive. In the past year, numerous demonstrations have sprung up about corruption, questionable electioneering, and Navalny, magnified across borders by major unrest in Belarus, the Azeri victory over Armenia in recent fighting, and other flare-ups within the states of the former Soviet Union. Additionally—and rightfully so, both for deterrence and allied assurance—NATO and the United States have conducted military exercises and maneuvers within the lands of allies and partners. This movement has made terrestrial-oriented Moscow nervous, even though the correlation of forces clearly shows that their relatively small number and array is no offensive threat to Russia. Regardless, the situation plays to both perceived and contrived Russian existential threat concerns.

    Russia’s formidable but still limited force array gives it several options. First and foremost, it signals its capability to take substantive offensive action against Ukraine. This does not mean, however, that the Kremlin intends to do so, despite heightened tensions and its overtly visible military deployments and posture. Most likely, this is aggressive, coercive posturing, designed to intimidate Ukraine and to push back on what it sees as an excessive U.S./NATO regional presence along Russia’s extended periphery and NATO’s support to partners such as Ukraine and Georgia. Fueling this seemingly angry posturing was Ukraine’s recent public request to be brought into NATO’s Membership Action Plan (MAP), which was akin to fluttering a red matador’s cape in the face of Moscow’s bull. It was the announced intention to bring Ukraine into the EU Association in 2013 that helped initiate the Maidan and the ugly sequence of events leading to Russia’s invasion of Ukraine and illegal annexation of Crimea in early 2014. Although Russia’s movements are likely a military demonstration, the real prospect of a very dangerous accident, incident, or provocation could inadvertently mutate into a “how did we get here?” confrontation between both heavily armed camps that, on the ladder of escalation, could in an extreme worst case involve nuclear weapons. The decision to rescind sending two U.S. warships into the Black Sea at this time was wise; Russia is extremely touchy about Crimea, and there is still plenty of NATO regional presence compared to 2014. When linked with the prospect of direct talks between Presidents Joe Biden and Vladimir Putin this summer, along with a senior-level Strategic Stability Dialogue, careful planning and messaging could help deescalate any additional force-on-force buildups. A key event to watch will be the major Russian Zapad-21 military exercise that will occur in late summer or early autumn 2021. It traditionally takes place in western Russia, including Kaliningrad, and also involves recently shaky Belarus.

    If Russia does undertake offensive operations in Ukraine, its options depend on its ultimate objectives. Moscow would have the initiative, as any conflict would begin with their offensive action. Presaging overt military operations would likely be an aggressive, non-kinetic cyber and electronic warfare effort to blind and confuse forward Ukrainian and regional NATO assets as well as its command and control. Moscow would have to decide if it wants to go big and seize major tracts of land, set limited territorial objectives, or bloody forward Ukrainian forces with hard-hitting cross-border punitive strikes. Seizing and holding major terrain deep in Ukraine would be especially difficult for a Russian military designed to strike deep but not hold major tracts of land, especially in contested terrain. Any offensive variation would have huge international and domestic implications for Russia, where its patriotic but increasingly discerning population could pressure the regime if they sensed that an assault of their difficult but still kindred Ukrainian neighbor was punitive rather than existential to Russia. This likely discontent would be amplified if Russian forces took major casualties, especially young conscripts, in a difficult-to-justify offensive fight against a much-improved Ukrainian military. A Western response would be significant and substantive, such as rapidly supplying Ukrainian forces with a flood of capable lethal weapons; at the same time, Russia would be diplomatically and economically assailed internationally in ways that would especially hurt Russia’s monied interests. In a worst-case scenario, U.S./NATO forces could be drawn into a dangerous escalatory fight that neither side wants, one that could rapidly spread across Russia’s vast, vulnerable periphery including the Arctic.

Kennan Institute

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