Russia’s Possible Invasion of Ukraine

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The Issue

If peace talks fail, the Russian military has several options to advance into Ukraine through northern, central, and southern invasion routes. But a Russian attempt to seize and hold territory will not necessarily be easy and will likely be impacted by challenges from weather, urban combat, command and control, logistics, and the morale of Russian troops and the Ukrainian population. The United States and its European allies and partners should be prepared for an invasion by taking immediate economic, diplomatic, military, intelligence, and humanitarian steps to aid Ukraine and its population and shore up defenses along the North Atlantic Treaty Organization’s (NATO) eastern flank.


Russian president Vladimir Putin continues to threaten an invasion of Ukraine with a major military buildup near the Russian-Ukrainian border and aggressive language. Russia has deployed offensive weapons and systems within striking distance of Ukraine, including main battle tanks, self-propelled howitzers, infantry fighting vehicles, multiple launch rocket systems, Iskander short-range ballistic missile systems, and towed artillery, as highlighted in Figures 1a and 1b. Putin has complemented this buildup with blunt language that Ukraine is historically part of Russia and that Kiev needs to return to the Russian fold.1 Russia’s threat is particularly alarming for at least two reasons. First, Russia could move its pre-positioned forces into Ukraine quickly. If fully committed, the Russian military is significantly stronger and more capable than Ukraine’s military, and the United States and other NATO countries have made it clear they will not deploy their forces to Ukraine to repel a Russian invasion. Even if diplomats reach an agreement, Putin has shown a willingness to dial up—and down—the war in Ukraine and threaten to expand the war, making the Russian threat persistent. Second, an invasion would mark a significant change in international politics, creating a new “Iron Curtain” that begins along Russia’s borders with Finland and the Baltic states and moves south through Eastern Europe, the Middle East, Central and South Asia, and finally to East Asia along China’s southern flank.

Consequently, it is important to understand how Russia could invade Ukraine, how specific political objectives may influence an invasion plan, the challenges an invasion may face, and what options the United States and its European partners have to respond. To help understand these dynamics, this brief asks several questions. What are Russian president Vladimir Putin’s objectives? What military options does Russia have, and what might an invasion look like? How should the United States and its allies and partners respond?

The brief makes two main arguments. First, if Russia decides to invade Ukraine to reassert Russian control and influence, there are at least three possible axes of advance to seize Ukrainian territory: a northern thrust, possibly attempting to outflank Ukrainian defenses around Kiev by approaching through Belarus; a central thrust advancing due west into Ukraine; and a southern thrust advancing across the Perekop isthmus. Second, if the United States and its European partners fail to deter a Russian invasion, they should support Ukrainian resistance through a combination of diplomatic, military, intelligence, and other means. The United States and its European partners cannot allow Russia to annex Ukraine. The West’s appeasement of Moscow when it annexed Crimea in 2014 and then orchestrated an insurgency in Eastern Ukraine only emboldened Russian leaders. In addition, Russian annexation of some or all of Ukraine would increase Russian manpower, industrial capacity, and natural resources to a level that could make it a global threat. The United States and Europe cannot make this mistake again.

The rest of this brief is divided into three main sections. First, it examines Russian political objectives. Second, the brief analyzes Russian military options. Third, it explores options available to the United States and its allies and partners.

Figure 1a: Russian Military Buildup near Yelnya, Russia

Figure 1b: Close-Up of Russian Military Buildup near Yelnya, Russia

Russian Political Objectives

The Kremlin wants what it says: an end to NATO expansion, a rollback of previous expansion, a removal of American nuclear weapons from Europe, and a Russian sphere of influence. However, Putin may accept less. The Kremlin’s primary goal is a guarantee that Belarus, Ukraine, and Georgia will never belong to a military or economic bloc other than the ones Moscow controls and that Russia will be the ultimate arbitrator of the foreign and security policy of all three states. In essence, this conflict is about whether 30 years after the demise of the Soviet Union, its former ethnic republics can live as independent, sovereign states or if they still must acknowledge Moscow as their de facto sovereign.

Ostensibly, the demand for an exclusive sphere of influence in Eastern Europe and the south Caucasus is to meet Russian security interests. The Kremlin has portrayed NATO expansion to the east as the original sin of post-Soviet international relations with the West that now must be rectified. Facts, alternate interpretations, and the security concerns of equally sovereign nations notwithstanding, Moscow claims that without such guarantees, it will use military force to protect its security interests.

Russian Military Options

Based on these political objectives, the Kremlin has at least six possible military options:

1. Redeploy some of its ground forces away from the Ukrainian border—at least temporarily—if negotiations are successful but continue to aid pro-Russian rebels in Eastern Ukraine.

2. Send conventional Russian troops into the breakaway regions of Donetsk and Luhansk as unilateral “peacekeepers” and refuse to withdraw them until peace talks end successfully and Kiev agrees to implement the Minsk Accords.

3. Seize Ukrainian territory as far west as the Dnepr River to use as a bargaining chip or incorporate this new territory fully into the Russian Federation. This option is represented in Figure 2a.

4. Seize Ukrainian territory up to the Dnepr River and seize an additional belt of land (to include Odessa) that connects Russian territory with the breakaway Transdniestria Republic and separates Ukraine from any access to the Black Sea. The Kremlin would incorporate these new lands into Russia and ensure that the rump Ukrainian statelet remains economically unviable.

5. Seize only a belt of land between Russia and Transdniestria (including Mariupol, Kherson, and Odessa) to secure freshwater supplies for Crimea and block Ukraine’s access to the sea, while avoiding major combat over Kiev and Kharkiv. This option is represented in Figure 2b.

6. Seize all of Ukraine and, with Belarus, announce the formation of a new tripartite Slavic union of Great, Little, and White Russians (Russians, Ukrainians, and Belarusians). This option would involve operations represented in Figure 2a as “phase one,” with Figure 2c representing “phase two” of this option.

Of these six options, the first two are the least likely to incur significant international sanctions but have limited chance of achieving a breakthrough on either NATO issues or the Minsk Accords due to their coercive nature. All other options bring major international sanctions and economic hardship and would be counterproductive to the goal of weakening NATO or decoupling the United States from its commitments to European security.

Options three through six could achieve another goal—the destruction of an independent Ukraine—whose evolution toward a liberal democratic state has become a major source of contention among the Kremlin’s security elites. Option three would have Russia control a substantial amount of Ukrainian territory but still leave it as an economically viable state. Option four leaves only an agrarian rump Ukraine but precludes occupying its most nationalistic areas. Option five leaves more of Ukraine free but still cuts its access to the sea and incurs fewer occupation costs. Options four and five—seizing a belt of land from Tiraspol to Mariupol—are complicated by the fact that there is no east-west running natural feature, river, or mountain range that could serve as a natural line of demarcation for this occupied land. The new border along this territory would run across countless fields and forests and be difficult to defend. Option six means occupying the entire country and dealing with the assimilation of a population of 41 million that may resist occupation actively and passively for years. It would require an occupation force of considerable size to control the population and man the new borders with NATO countries. Ukrainians in any occupied territory can expect forced Russification that the nation experienced under such rulers as Catherine the Great, Alexander II, Stalin, and Brezhnev.

Possible Invasion Routes

Ideological preparation of Russian society for a conflict with Ukraine has been ongoing since at least 2014, with Kremlin propaganda portraying Ukraine as a proto-fascist, neo-Nazi state. In July 2021, a public letter by President Putin asserted that Russians and Ukrainians are the same people and castigated Ukraine’s authorities for justifying independence by denying its past.2 The Russian military made President Putin’s article compulsory reading for its soldiers.3 This was followed in October by a letter in the newspaper Kommersant by Russian Security Council vice-president Dmitry Medvedev, which used antisemitic tones to delegitimize the current Ukrainian leadership as extremist, corrupt, and foreign controlled.4

With an ideological basis for action in place, the next step is to create a casus belli—justification for war—consistent with the Kremlin-manufactured image of Ukraine. Pretexts for an attack could range from a straightforward breakdown of security talks to a stage-managed incident similar to the provocations at Mukden, Gleiwitz, and Mainila that provided justification for Japan’s invasion of Manchuria, Germany’s invasion of Poland, and the Soviet Union’s attack on Finland, respectively. This is why the bizarre claim of Defense Minister Sergey Shoigu posted on the Kremlin’s official website of American mercenaries preparing a “provocation” with chemical weapons in Ukraine is ominous and might foreshadow just the type of “incident” the Kremlin would prepare.5

Once there is a casus belli, cyberattacks will likely follow to degrade Ukraine’s military command and control systems and public communications and electrical grids. Next, kinetic operations will likely begin with air and missile strikes against Ukraine’s air force and air defense systems. Once air superiority is established, Russian ground forces would move forward, slightly preceded by special operations to degrade further command and control capabilities and delay the mobilization of reserves by conducting bombings, assassinations, and sabotage operations.

The scheme of maneuver of a Russian military invasion of Ukraine will likely be influenced by which of the above political goals the Kremlin wishes to achieve, the geography of the land and cities to be fought over, and the transportation routes to bring up logistics. If the Kremlin wishes to exercise options three, four, or six, and taking into consideration primary geography and logistics, there are three likely axes of advance to seize Ukrainian territory east of the Dnepr River, with the river as either a limit of advance or the first phase line of a larger invasion.

  • Northern Route: Russia could advance toward Kiev along two routes. The first would be 150 miles by road through Novye Yurkovichi, Russia; Chernihiv, Ukraine; and into Kiev, Ukraine. The second would be a 200-mile thrust through Troebortnoe, Russia; Konotop, Ukraine; Nizhyn, Ukraine; and into Kiev.6 If Minsk were to acquiesce to the use of its road and rail networks, the Russian army could outflank Ukrainian defenses around Kiev and approach them from the rear via a 150-mile axis of advance from Mazur, Belarus, to Korosten, Ukraine, and finally to Kiev.

  • Central Route: Russia could also advance due west along three routes. The first might include a 200-mile axis that moves through Belgorod, Russia; Kharkiv, Ukraine; Poltava, Ukraine; and finally to Kremenchuk, Ukraine. The second might include a 140-mile axis thrust through Donetsk, Ukraine to Zaporizhzhia, Ukraine; and possibly also another thrust from Donetsk to Dnipro, Ukraine. The third might involve Russian forces advancing along the coastline toward Mariupol, Berdyansk, and the Perekop isthmus connecting Crimea to Ukraine.

  • Southern Route: Russia could also advance across the Perekop isthmus to take Kherson and the source of freshwater for Crimea and simultaneously toward the vicinity of Melitopol to link up with Russian forces advancing along the coast of the Sea of Azov. If Russia was to attempt option five, this would be the main attack coupled with the assault along the coastline toward Mariupol and Berdyansk. But it would be hardest to sustain logistically due to the lack of a railway running along the Sea of Azov coast and the main direction of advance.

Figure 2 highlights possible invasion routes. All of these routes, except the coastal one, parallel existing rail lines. This is essential since Russian army logistics forces are not designed for large-scale ground offensives far from railroads.7 If Russia’s objectives include denying Ukraine future access to the sea, it will have to seize Odessa. Some predict that this would be accomplished via amphibious and airborne landings near Odessa, which link up with mechanized forces approaching from the east. If Russia intends to conquer the entire country, its forces would need to seize Odessa (whose port facilities would ease Russian logistics) and also cross the Dnepr River at several points to march and fight an additional 350 to 700 miles further west to occupy all of Ukraine up to its borders with Poland, Slovakia, Hungary, Romania, and Moldova.

Figure 2: Possible Russian Invasion Routes

Russian Prospects of Success

Mechanized attacks are not always as rapid as attackers hope. Two of the quickest movements of armored forces in history—German general Heinz Guderian’s punch through the Ardennes and seizure of Dunkirk in May 1940, and the U.S. and coalition advance from the Kuwait border to Baghdad in 2003—each averaged approximately 20 miles per day. Movement against a determined foe in winter conditions with limited daylight could reduce that rate of advance significantly.

With enough troops, firepower, logistics, time, and national will, as well as no outside interference, Russia could grind forward until its military achieves the Kremlin’s political objectives. Russia’s military outnumbers Ukraine’s military in the air and on the ground, Russia gained extensive experience in conducting combined-arms operations in Syria, and the terrain favors offensive mechanized warfare. However, the true calculation of military success can only be taken after a clash of arms begins. In addition, there are several intangibles—such as weather, urban combat, command and control, logistics, and morale—that may play a significant role in the initial stages of a war.

Weather: An invasion that begins in January or February would have the advantage of frozen ground to support the cross-country movement of a large mechanized force. It would also mean operating in conditions of freezing cold and limited visibility. January is usually the coldest and snowiest month of the year in Ukraine, averaging 8.5 hours of daylight during the month and increasing to 10 hours by February.8 This would put a premium on night fighting capabilities to keep an advance moving forward. Should fighting continue into March, mechanized forces would have to deal with the infamous Rasputitsa, or thaw. In October, Rasputitsa turns firm ground into mud. In March, the frozen steppes thaw, and the land again becomes at best a bog, and at worst a sea of mud. Winter weather is also less than optimal for reliable close air support operations.

Urban Combat: While much of the terrain east of the Dnepr River includes rural fields and forests, there are several major urban areas that a Russian mechanized force would have to either take or bypass and besiege. Kiev has almost 3 million inhabitants, Kharkiv has roughly 1.5 million, Odessa has 1 million, Dnipro has almost 1 million, Zaporizhia has 750,000, and even Mariupol has almost 500,000.9 If defended, these large urban areas could take considerable time and casualties to clear and occupy. In the First Chechen War, it took Russian forces from December 31, 1994, to February 9, 1995, to wrestle control of Grozny, then a city of less than 400,000, from a few thousand Chechen fighters.10 In the Second Chechen War, the siege of Grozny also took six weeks.

Therefore, the best course of action for Russian troops would be to bypass urban areas and mop them up later. However, Kharkiv is just over the border from Russia and is a major road and railroad junction. If Russian forces did not control Kharkiv, it would seriously diminish their logistical capability to support a central thrust toward the Dnepr River and beyond. Furthermore, Kiev poses a similar challenge and, as the nation’s capital, possesses great symbolic value for whichever side holds it. Russia may be unable to avoid sustained urban combat in several major metropolitan areas (and the resulting high casualties) if it attempts more than a punitive incursion into Ukraine.

Command and Control: There is a Russian expression: “the first blini is always a mess.” In the case of an invasion of Ukraine, Russia will be conducting its largest combined arms operation since the Battle of Berlin in 1945. The 2008 Russo-Georgian War saw just five days of combat and engaged 70,000 Russian soldiers.11 In Syria, the primary maneuver forces included Syrian ground units, with help from Lebanese Hezbollah, militia forces from neighboring countries such as Iraq and Afghanistan, private military companies such as the Wagner Group, and Iran’s Islamic Revolutionary Guard Corps-Quds Forces. But Russia did not deploy significant numbers of conventional forces. Approximately 120,000 Russian soldiers are mobilized near Ukraine, with tens of thousands more ready to deploy into combat.12 It will be a challenge for Russian command and control to first move all of these forces into their attack positions with proper march discipline. It will also be difficult for Russia to maintain that discipline during the attack so that the massive amounts of vehicles and soldiers moving on a limited number of slippery and poor roads and often at night do not become one gargantuan traffic jam.

The coordination of airborne and amphibious assaults will prove another challenge. While airborne forces could be dropped along the Dnepr River to seize crucial bridges, how long would they be able to hold out while armored forces try to reach them over winter roads? The same applies for amphibious forces attempting to outflank Ukrainian defenses near Mariupol or to seize Odessa. Black Sea hydrography and coastal topography provide few good landing sites for amphibious forces, and once landed, they would be hard to sustain.13 Without proper coordination and rapid advance of armored forces, any airborne or amphibious assault as part of the invasion could become a “bridge or beach too far” for Russian forces. Figures 3a, 3b, and 3c highlight ships from the Russian navy’s Black Sea Fleet, including landing ships and corvettes that could be used in an amphibious assault into Ukraine.

Figure 3a: Sevastopol Bay, Crimea

Figure 3b: Close-Up of Russian Landing Ships in Sevastopol

Figure 3c: Close-Up of Russian Maritime Vessels in Sevastopol

The Russian military also has limited experience in coordinating a large number of aircraft that will support the ground attack. Russian air operations in Syria and Chechnya do not compare with the number of sorties that could be required in Ukraine across a front possibly several hundred miles wide. This will be the first time since World War II that Russia’s ground forces will face a modern mechanized opponent, and its air forces will face an opponent with a modern air force and air defense system. Consequently, Russian forces will likely face notable challenges in command, control, communications, and coordination.

Logistics: The initial attack will likely be well supported with artillery and air support, leading to several breakthroughs in Ukrainian defenses. However, once combat units expend their initial stores of ammunition, fuel, and food, the real test of Russian military strength will begin—including Russia’s ability to sustain the advance of a massive mechanized force over hundreds of miles of territory. Kiev and the Dnepr River crossings are at least 150 to 200 road miles from the Russian border, and its army will require at least several days of fighting to reach them. Before that, they will undoubtedly have to resupply, refuel, and replace combat losses of men and material at least once, which will require an operational pause.

In his article “Feeding the Bear,” Alex Vershinin argues that there are serious logistical challenges to a Russian invasion that is supposed to roll over the Baltic states in 96 hours and present the West with a fait accompli. Russia has built an excellent war machine for fighting near its frontier and striking deep with long-range fires. However, Russia may have trouble with a sustained ground offensive far beyond Russian railroads without a major logistical halt or a massive mobilization of reserves.14 As the operational depth in Ukraine is far greater than in the Baltics, a Russian invasion of Ukraine could be a longer affair than some anticipate due to the time and distance to bring up supplies. If the invasion is not concluded quickly due to a combination of weather, logistics, and Ukrainian resistance, how might this impact Russian morale?

Morale: There are two levels of morale on each side to consider: the morale of individual soldiers and the morale of each country and its people. At the individual level, will a Ukrainian soldier who believes he or she is fighting for their homeland have an advantage over a Russian soldier whose motivation for fighting may vary? For the Ukrainian nation as a whole, how strong is their sense of a unique national identity to resist what could be a long, destructive, and bloody struggle? The answers cannot be known until the war begins. However, should war come, one factor influencing morale will be time. The longer the Ukrainian army resists the Russians, the greater its confidence may grow as well as its institutional knowledge of how to fight this enemy. In addition, the longer the war continues, the greater may be the level of international support and the greater the chance of increased arms transfers to help turn the tide on the battlefield.

For Russia, the longer the war continues and the greater the casualties, the greater the chance of undermining Russian morale from the level of the basic soldier to Russian society writ large. Approximately one-third of Russian ground forces consist of one-year conscripts.15 These conscripts serve alongside professional soldiers, or kontraktniki, under a system of hazing known as the dedovshchina. This system is infamous for its abuses up to and including murder, which can erode unit cohesion. Additionally, heavy casualties will need quick replacements, and reservists brought to reinforce frontline units have received little recent training. As the number of professional soldiers decreases due to casualties, and reservists and conscripts increase on the front line, the chance of poor unit cohesion at the soldier level will rise. If casualties and even defeats mount, problems of cohesion at the front could be reflected in public unrest at home.

Every Kremlin ruler knows that one of the quickest ways to end a Russian dynasty or regime is to lose a war. While early Soviet assessments of the war in Afghanistan were hopeful, they eventually turned gloomy. At a Politburo meeting on October 17, 1985, for example, Soviet leader Mikhail Gorbachev read letters from Soviet citizens expressing growing dissatisfaction with the war in Afghanistan—including “mothers’ grief over the dead and the crippled” and “heart-wrenching descriptions of funerals.”16 As the Soviet war in Afghanistan dragged on, the costs—including in blood and money—were too high and outweighed any geostrategic benefits. Over the course of the war, nearly 15,000 Soviet soldiers were killed, and another 35,000 were wounded.

Russian families are sure to resent their soldiers being used as cannon fodder, and the ubiquitous presence of cell phone cameras and videos in today’s world will expand soldiers’ complaints beyond their units. Therefore, the question for the Kremlin will be: the longer the war grinds on and society reacts to casualties and economic duress, how much are their initial objectives worth to them?

The U.S. and Western Response

A Ukraine that is willing to fight for itself is a Ukraine worth supporting. While the Ukraine of 2022 is not a perfect democracy, neither was Poland in 1939 when Britain and France decided that their principles and security interests made it necessary to draw the line against Nazi aggression along its borders. The key to thwarting Russian ambitions is to prevent Moscow from having a quick victory and to raise the economic, political, and military costs by imposing economic sanctions, ensuring political isolation from the West, and raising the prospect of a prolonged insurgency that grinds away the Russian military. In this war, Russia might have the watches, but the West and Ukraine may have the time.

Washington’s goal should be to deter Russian conventional operations in Ukraine by punishment—not denial. Deterrence by denial involves preventing an opponent from taking an action, such as seizing territory, by making it infeasible or unlikely to succeed. Absent a major U.S. and European military deployment to Ukraine, which President Biden has already ruled out since Ukraine is not a member of NATO, Ukrainian forces cannot prevent a rapid deployment of Russian forces into Ukraine. Deterrence by punishment, however, involves preventing an opponent from taking an action because the costs—such as nuclear weapons, economic sanctions, or an insurgency—are too high. Deterrence by punishment is possible if led by the United States. The United States and its European allies and partners should publicly and privately continue to communicate to Moscow that a conventional attack on Ukraine would initiate crippling sanctions from Western countries, deepen Russia’s political isolation from the West, and trigger a Western-backed insurgency against Russian forces in Ukraine. The United States would have to take the lead. The populations of several European countries, such as Germany and Austria, have noted that they would prefer to remain neutral in a war with Russia.17

If deterrence fails and Russian forces invade Ukraine, the United States and its allies and partners should conduct several immediate steps:

  • Implement severe economic and financial sanctions against Russia, including cutting Russian banks off from the global electronic payment messaging system known as SWIFT.

  • Enact a Twenty-First Century Lend-Lease Act to provide Ukraine with war materiel at no cost. Priority items would include air defense, anti-tank, and anti-ship systems; electronic warfare and cyber defense systems; small arms and artillery ammunition; vehicle and aircraft spare parts; petroleum, oil, and lubricants; rations; medical support; and other needs of a military involved in sustained combat. This aid could occur through overt means with the help of U.S. military forces, including special operations, or it could be a covert action authorized by the U.S. president and led by the Central Intelligence Agency.

  • Provide intelligence to allow Ukraine to disrupt Russian lines of communication and supply, as well as warning of airborne and amphibious attacks and locations of all major units.

  • Offer humanitarian support to help Ukraine deal with refugees and internally displaced persons. This assistance may also need to be extended to NATO allies on Ukraine’s borders for refugees fleeing westward.

  • Provide economic support, including energy, to Ukraine and NATO allies due to the expected disruption of Russian gas flows to Europe.

  • Conduct public diplomacy and media broadcasts to Ukraine and globally, including in Russia, to portray accurately what is happening.

  • Apply diplomatic pressure on Belarus to deny Russia access to its territory to attack Ukraine. This is critically important because Russian use of Belarus’ rail and road networks would threaten a strategic turning movement of Ukraine’s northern flank.

  • Coordinate with nongovernmental organizations and the International Criminal Court to document all war crimes inflicted on the Ukrainian people and to demand redress once the war is over. What happened to the Syrian people should not happen again.

The United States and NATO should be prepared to offer long-term support to Ukraine’s resistance no matter what form it ends up taking. There has already been public debate about unconventional warfare support to Ukraine should part or all of Ukraine be occupied.18 However, this option must be approached with a clear understanding of what is possible to achieve—and what might not be possible. Russia has historically proven adept at destroying armed resistance movements, and given enough time, it can do so again. Its methods against a Ukrainian resistance will be swift, direct, and brutal.19 Any sanctuary that the resistance uses, whether it is in rump Ukrainian or NATO territory, could be subject to Russian overt or covert attack. Therefore, it would require the protection of substantial conventional forces to deter Russian actions in NATO territory. Furthermore, whatever portion of Ukraine’s border Russia may occupy could quickly resemble the Iron Curtain of the twentieth century, featuring heavy fortifications. The Berlin Wall was a heavily-guarded concrete barrier, which included anti-vehicle trenches, mesh fencing, barbed wire, a bed of nails, and other defenses. It will be hard to establish supply lines for a resistance across such an obstacle from any sanctuary.

While the Russians have been adept at anti-resistance operations, they are not adept at extinguishing nationalism. Any support to occupied Ukraine should also include means to maintain Ukrainian’s national identity, history, and language among its citizens. While armed resistance would hearken to the 1980s support provided to the Afghan mujahedin, this type of support to preserve the Ukrainian nation would be more in keeping with the help provided to Polish Solidarity during its struggles for freedom.20

In addition, Ukraine could potentially prevent Russia from seizing and holding all or most of its territory with U.S. and other international aid. For example, Ukraine could keep most of its maneuver forces back far enough from initial Russian breakthroughs so that they are not encircled. As Russian forces advance west, Ukraine should gain intelligence to determine Russia’s main thrusts, conduct deep strikes against its supply lines to force them into an operational pause, and once they are stopped, envelop and counterattack them. Cities should hold out as long as possible. In the case of Kharkiv, railroads and bridges inside the city should be utterly destroyed prior to capitulation to further degrade Russian lines of communication. If the Russian military approaches the Dnepr River, its multiple dams could be opened and low-lying areas flooded. Airborne and amphibious assaults should be isolated immediately. Ukraine’s goal should be to prevent Russia from making any significant advances before the onset of the Rasputitsa, or thaw.

Once mechanized movement is ground to a halt by mud and supply problems, airborne and amphibious pockets can be eliminated, and Ukraine will have had enough time to mobilize and deploy its approximately 900,000-man reserve force. Hopefully, international aid will also begin arriving in the form of weapons systems to prevent Russia from achieving air superiority over Ukraine and allowing it to continue to strike deep into the Russian army’s rear to attrit reinforcements and supply lines. As weeks turn into months, international economic and financial sanctions should begin to take effect. The Kremlin would then be faced with a long war, on the battlefield and off it, with little end in sight.

A New Iron Curtain

The current situation bears an eerie resemblance to Soviet decisionmaking in 1979 to invade Afghanistan. In that case, a small coterie in the Politburo made the decision on their own based on faulty intelligence, poor perceptions of the international environment, overly optimistic scenarios of success, and little comprehension of the international political and economic costs they would face. A risk-versus-reward calculation of Russia achieving its political objectives should discourage it from an invasion. Its best option would be to continue to rattle sabers, pursue diplomatic negotiations, and aid pro-Russian insurgents in Eastern Ukraine—but to refrain from a conventional invasion. However, President Putin has made high-profile demands and threats that will be very hard to retreat from. Should miscalculation, emotion, and poor crisis management overcome rational calculations and lead to conventional war, the international landscape will likely witness a dramatic change.

In his famous Iron Curtain speech on March 5, 1946, British prime minister Winston Churchill spoke darkly that “a shadow has fallen upon the scenes” of Europe that pitted democratic states against authoritarian ones. “From Stettin in the Baltic to Trieste in the Adriatic,” Churchill remarked, “an Iron Curtain has descended across the Continent.”21 A new Iron Curtain would be even more dangerous—spanning Europe, the Middle East, and Asia and incorporating a new axis of authoritarian regimes that includes Russia, China, Iran, and North Korea. This new dividing line would move along Russia’s borders with Finland and the Baltic states along NATO’s eastern flank; cut through Russian- and Iranian-supported countries in the Middle East and Central Asia, such as Syria and Kazakhstan; and snake along China’s borders with India through East Asia to the South China Sea. If Russia were to invade Ukraine, the United States and other European states would need to rush soldiers and materiel to NATO’s eastern flank—such as Latvia, Lithuania, Estonia, and Poland—in case the Russians threatened to advance westward. Russia might also try to instigate a crisis in one or more of the Balkan states to split American and European attention and resources. In Asia, Taiwan would likely be on alert about possible Chinese movements to take the island.

Countries such as Russia and China admire strength and have little respect for weakness—including military weakness. Competition could increasingly become a struggle between rival political, economic, and military systems—between authoritarian, state-controlled systems and democratic ones. The illiberalism at the root of Chinese, Russian, Iranian, and North Korean systems is antithetical to Western Enlightenment values. They eschew freedom of the press, freedom of religion, free markets, and democracy. As Thomas Jefferson remarked, “Freedom of religion; freedom of press; and freedom of person. . . . These principles form the bright constellation, which has gone before us and guided our steps through an age of revolution and reformation.”22 They were critical in winning the Cold War against the Soviet Union, and they are just as important today.

“If the Western Democracies stand together in strict adherence to the principles of the United Nations charter, their influence for furthering these principles will be immense and no one is likely to molest them,” Churchill remarked in his Iron Curtain speech. “If however they become divided or falter in their duty and if these all-important years are allowed to slip away then indeed catastrophe may overwhelm us all.”23 Hopefully, reason will prevail in Moscow, and Russia will not invade Ukraine. If there is an invasion, however, the United States and its allies and partners need to be prepared to resist tyranny.

Philip G. Wasielewski recently retired after a 31-year career as a paramilitary operations officer in the Central Intelligence Agency. Seth G. Jones is senior vice president and director of the International Security Program at the Center for Strategic and International Studies (CSIS) in Washington, D.C., and author most recently of Three Dangerous Men: Russia, China, Iran, and the Rise of Irregular Warfare (W.W. Norton, 2021).

The authors give special thanks to Joe Bermudez and Jennifer Jun for their assistance with satellite imagery analysis, as well as to Jared Thompson for his outstanding research assistance. The authors also thank Jeeah Lee and William Taylor for their exceptional editorial and graphic design support.

This brief is made possible by general support to CSIS. No direct sponsorship contributed to this brief.

CSIS Briefs are produced by the Center for Strategic and International Studies (CSIS), a private, tax-exempt institution focusing on international public policy issues. Its research is nonpartisan and nonproprietary. CSIS does not take specific policy positions. Accordingly, all views, positions, and conclusions expressed in this publication should be understood to be solely those of the author(s).

© 2022 by the Center for Strategic and International Studies. All rights reserved.

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Seth G. Jones
Senior Vice President; Harold Brown Chair; and Director, International Security Program

Philip G. Wasielewski