How Could the War in Ukraine End?

Table of Contents

1. Neither side has enough manpower and equipment to end the war quickly

2. Ukraine probably can’t make up for the lack of equipment and manpower with combined arms warfare

3. Only a catastrophic mistake by one side could result in a quick end to the war and that’s unlikely

4. The scenario of a long but one-sided war ending with a clear victory by one side

5. As long as neither side commits significantly more resources than the other, a long war ending in a stalemate is more likely

6. The Biden administration’s plan and why it will probably fail

7. Credibility and the logic of escalation

8. The scenario of a runaway escalation ending with a decisive Russian or Ukrainian victory

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One year after Russia launched a full-blown invasion of Ukraine, which almost everyone thought would be over in a few weeks (at least as far as large-scale military operations were concerned), I think the dominant fact about the current state of the war is that none of the parties involved — by which I mean not only Russia and Ukraine but also the West — has a realistic plan to end it.

In a way, this is understandable. It’s very difficult to predict what is going to happen in the short-run, let alone in the long-run, so it’s very tempting to give up on trying to make predictions about how the conflict will end, to set oneself short-term goals and to focus on what one should do to achieve them without thinking about how it could bring the war to a conclusion one deems acceptable in the long-term.

However, I think it’s a mistake and that it’s important to do so, because focusing only on the short-term is the best way to make sure that, little by little and without realizing it, events take a direction we hadn’t foreseen and we end up somewhere nobody wants to go. This has been the recipe for many foreign policy disasters and we should be worried that it’s going to happen again.

When it comes to the war in Ukraine, many people take part in the policy debate but aren’t willing to make any kind of predictions, which I think is a bit like showing up to a ball when you’re not willing to pay the price of admission. In this essay, I will therefore review the different possible scenarios about how the war could end and, to the extent that I’m able to, assess how likely they are.

Neither side has enough manpower and equipment to end the war quickly

It’s clear that, at this point, neither side is interested in negotiations because both still think they can improve their situation militarily at a lower cost than what they would have to accept to reach a negotiated settlement now. Thus, for the war to end quickly, at least one side would have to revise that view in the next few months.

This could happen if one side achieved a decisive breakthrough that would compel the other to accept a negotiated settlement on terms it deems acceptable or, in the absence of such a breakthrough, decided that the expected cost of continuing to fight was now greater than the cost of the compromises it would have to make in order to reach a negotiated settlement. I don’t think either scenario is very likely.

A decisive breakthrough seems unlikely to me to me because I don’t think either side has enough manpower and equipment to achieve it. My argument is that, based on what happened so far, it’s clear that in this war the defending side enjoys a large advantage that requires the attacking side to have a large superiority in manpower and equipment.

If Russia initial assault, conducted with trained and well-equipped professional soldiers with plenty of ammunition against relatively unprepared and poorly equipped Ukrainian forces, didn’t succeed I think neither Ukraine nor Russia is likely to achieve a decisive breakthrough now that both sides are dug in and that neither can hope to achieve the relative advantage in manpower and equipment Russia initially had except very locally.

This argument is admittedly based on very crude calculations and neglects various factors such as skill, morale and the quality of the equipment used by each side, so maybe it’s mistaken, but I don’t think so. It’s not that I think those factors don’t matter, but I don’t believe they will be enough to make up for the fact that in strictly quantitative terms neither side is likely to enjoy anything like the kind of advantage that Russia initially had, which still wasn’t enough.

It’s not just a matter of the difficulty for either side to achieve a sufficient relative advantage in manpower and equipment, they will also have a hard time accumulating enough in absolute terms to achieve what I call a decisive breakthrough. Indeed, to capture large swathes of territory that are defended by well-manned heavily fortified, you don’t just need to have a lot more equipment and manpower than the defending side, you also need to have enough. I don’t think either side has enough.

A German Leopard 2A6 during a NATO exercise in 2012

To be sure, the West recently committed to deliver a significant number of armored vehicles to Ukraine, but at the end of the day if we focus on main battle tanks, we’re only talking about less than 100 Leopard 2s and maybe a bit more Leopard 1s that will only arrive in Ukraine and become available for deployment on the battlefield very gradually.

The 14 Challenger 2s that the UK has promised won’t make a big difference and were mostly sent to nudge Berlin into authorizing the re-export of Leopard 2s by other countries. The same thing is true for the 31 Abrams promised by the US, which moreover are widely expected to be a logistical nightmare for Ukraine and probably won’t arrive until the end of the year.

Of course, NATO countries will no doubt send more eventually, but due to political constraints, the fear of provoking a reaction in Russia and bureaucratic inertia, it will take time and be gradual, making it hard for Ukraine to build up a critical mass of armor since in the meantime it will suffer losses. In the end, while people focus on main battle tanks, the infantry fighting vehicles and armored personnel carriers recently promised by the West, such as the 109 Bradleys and 90 Strykers committed by the US so far, may well matter more if only because they will arrive much sooner.

The problem is not just going to be the lack of a critical mass of armor, but also the lack of ammunition for artillery systems, which is going to be a major limiting factor for both sides but probably even more so for Ukraine. In fact, the lack of armor will make the lack of ammunition for artillery systems even more critical, because artillery is often used to make up for a lack of armor.

Ukraine probably can’t make up for the lack of equipment and manpower with combined arms warfare

US officials seem aware of the problem, which is why they’re trying to make up for the lack of ammunition for artillery systems by turning the Ukrainian military into a force that fights more like the US military, which doesn’t rely on artillery as much and more on maneuver to achieve its objectives.

The problem is that I have serious doubt it can work, because the US military:

1. always had a lot of armor whereas Ukraine doesn’t;

2. has the best logistics in the world in comparison to which Ukraine’s logistic capabilities are very limited especially since it has to use disparate weapon systems that come from many different sources;

3. always enjoys total air superiority whereas Ukraine doesn’t and can only hope it will have enough air defense to prevent Russia from exploiting its advantage in air power;

4. its soldiers have years of training in combined arms tactics using the same equipment;

5. it has rarely had to fight an enemy that was entrenched in well-manned, heavily fortified positions.

But then again, I’m no military expert and it’s possible that I will be proven wrong, though I can’t find any obvious flaws in my argument. Of course, it could simply be because I lack the domain-specific knowledge to detect them, but since military experts disagree on what to expect I have no choice than to rely on my own judgment and when I read about previous conflicts I don’t find any reason to think it’s fundamentally mistaken.

For instance, General Norman Schwarzkopf, who led the coalition forces during the Gulf War, explained that he insisted on having a much larger force at his disposal when he learned that he was going to be asked to attack the Iraqi forces in Kuwait on the grounds that as a rule the attacker should outnumber the defender by 3 to 1 and 5 to 1 if the defender is occupying fortified positions.

Yet the coalition forces presumably enjoyed a far greater advantage over Iraq in terms of skill, quality of their equipment and morale at the time than Ukraine does over Russia today. This suggests that even forces that are extremely skilled in combined arms warfare, have total air superiority, the best logistics in the world and much better equipment than their opponent are wary of attacking without overwhelming numerical superiority.

Schwarzkopf eventually won the argument and, when the ground invasion started, the coalition forces vastly outnumbered the troops that Iraq had to oppose them. Indeed, according to a survey commissioned by the US Air Force after the war to evaluate its performance (see in particular chapters 4 and 5 of part II), the Iraqi force was reduced to between 200,000 and 220,000 after the air campaign that preceded the ground invasion, less than 1/3 the size of the coalition forces.

The disparity in armor and artillery was less impressive in purely quantitative terms, though it was probably still significant, but the coalition had total control of the air. Moreover, many Iraqi units that survived the air campaign were demoralized and didn’t fight back, so those figures overestimate the actual opposition faced by coalition forces.

The overall force ratio can be misleading though, for locally coalition forces didn’t always enjoy a large numerical advantage and, in some cases, they were even outnumbered by forces that actually fought back. It’s sometimes argued that, since coalition forces prevailed against Iraqi units that used Soviet equipment while suffering almost no losses even in those cases (such as during the Battle of 73 Easting), it shows that Western technological superiority is so overwhelming that even a relatively small number of Western armored vehicles will allow Ukraine to win decisively.

There are several problems with that argument. First, while it’s true that locally coalition forces didn’t always enjoy overwhelming numerical superiority and still won decisively with a historically low rate of loss even when that happened, it doesn’t follow that the overall force ratio was not relevant.

Indeed, as Schwarzkopf explains in the interview linked to above, he was only able to execute the massive envelopment of the Iraqi forces in Kuwait that became known as the “left hook” because he was given such a huge number of troops and equipment backed by the most impressive logistical operation in the history of warfare.

Otherwise, as he explains, he would have had no choice but to carry out a frontal attack that could have resulted in the destruction of the coalition forces and at any rate would have resulted in a much higher rate of loss. There would have been no Battle of 73 Easting because the Second Armored Cavalry Regiment could not have surprised the Iraqi Republican Guard by attacking it from the West.

Moreover, this paper by Stephen Biddle makes a very convincing case that, while Western technological superiority was important, coalition forces were only able to achieve such impressive results during Operation Desert Storm because the greater technological sophistication of their equipment interacted with their superior skills, air superiority and Iraqi mistakes to produce a far greater difference in outcome than technological superiority alone or even all those factors together could have achieved if they combined linearly.

As Biddle points out, the result of simulations carried out after the war suggests that, even keeping the terrain, technological advantage of the US forces and indirect effects of the coalition’s air superiority constant, the outcome of the Battle of 73 Easting could have been very different if the Iraqi defending forces had not made several mistakes, if the US forces had been less offensively skilled or if they hadn’t been able to rely on air support. In the scenario where the Republican Guard doesn’t make any mistake, the attacking force is almost wiped out despite its technological advantage, even when offensive skill and air support are kept constant.

Presumably, in a less favorable terrain (which is the case in most places where Ukraine might launch a counter-offensive against Russia), without the coalition’s logistics to support its armor (which Ukraine can’t hope to match) and without the indirect effects of air superiority (which Ukraine lacks), this would be even more true.

Indeed, not only did were the terrain and meteorological conditions at 73 Easting particularly well-suited to take advantage of the coalition’s technological superiority (other simulations of the battle that were made with the same model also suggest that the weather could have made a huge difference), but some of the mistakes committed by the Republican Guard were compounded by the indirect effects of the coalition’s air superiority and it probably wouldn’t have been possible to move so fast and catch the Iraqi by surprise without the coalition’s superior logistics.

Abrams tanks during Operation Desert Storm, with a Bradley and a logistics convoy in the background

Since moreover the Ukrainian armed forces can’t be expected to match the coalition forces in offensive skills because they haven’t been training on Western equipment for years, and since I don’t think the Russian armed forces should be expected to consistently make the kind of mistakes committed by the Iraqi Republican Guard at 73 Easting (lack of properly arranged defensive positions, lack of artillery support and lack of advance warning in case of attack), there is no reason to expect that Ukraine will be able to achieve offensive victories without suffering heavy losses.

Biddle’s paper illustrates the dangers of drawing lessons about the Russo-Ukrainian war from a handful of engagements in a war that was fought in completely different conditions. This is made clear by simulations, which allows us to vary some of those conditions and observe what difference it makes, but it’s also suggested by the results of live military exercises. Indeed, units equipped with Abrams have often been opposed to forces equipped with T-72s in exercises conducted at the US Army’s National Training Center and, according to Biddle, they almost always lost.

The conclusion I draw from Biddle’s paper is that, although Western armored vehicles will no doubt increase the capabilities of the Ukrainian armed forces significantly, it’s unreasonable to assume they will allow them to achieve anything close to what coalition forces were able to do against Iraqi forces during Operation Desert Storm. Those vehicles are not wunderwaffe and will not help Ukraine achieve a decisive breakthrough unless they’re sent in much greater numbers quickly.

Nor should we assume that, although the Ukrainian armed forces won’t be able to exploit the technological superiority of Western armored vehicles in the same way because they are less used to them, don’t have the US military’s logistics to support them, lack air superiority and the Russians are unlikely to make the same mistakes as the Iraqi forces in Kuwait, the coalition’s victory against Iraq was so lopsided that we should still expect Western equipment to allow Ukraine to overcome the lack of a large numerical advantage in manpower and equipment.

Indeed, Biddle’s argument is that the skill of the attackers does not combine with the other factors linearly but interacts with them in a highly nonlinear way (which is supported by data from both simulations and exercises), so in a scenario where the attackers are less skilled and the other factors, such as air superiority, are different you shouldn’t expect the outcome to be just somewhat worse but completely different. Schwarzkopf’s point about the importance of the coalition’s overwhelming numerical superiority at the theater level suggests the same conclusion.

The same argument equally applies to Russia and perhaps even more. While it probably has significantly more manpower now than it did at the beginning of the invasion after the partial mobilization, it still won’t be enough to achieve the kind of ratio of forces that is necessary to overwhelm well-defended positions.

It has suffered heavy losses in men and equipment and I doubt the Russian armed forces can succeed with poorly trained conscripts when they failed last year with better equipped professional soldiers who had years of training, even if they focus on just one direction like the Slovyansk-Kramatorsk area instead of diluting their forces by launching large-scale offensives on multiple fronts again.

Only a catastrophic mistake by one side could result in a quick end to the war and that’s unlikely

Moreover, it’s important to understand that, given how I defined “decisive breakthrough”, achieving a decisive breakthrough is a very high bar for both sides. For instance, even if Ukraine managed to take Melitopol this year (thereby cutting the Russian land bridge to Crimea and putting the peninsula at risk), I don’t think it would induce Russia to accept a negotiated settlement because I don’t think that Ukraine would be willing to make the necessary compromises and in particular to give up the goal of taking back Crimea.

Similarly, even if Russia somehow managed to take Slovyansk (which seems just as unlikely as Ukraine’s capture of Melitopol), I don’t think it would be enough for Ukraine to accept a negotiated settlement because I don’t think that in that scenario Moscow would be willing to scale down its demands enough to make them acceptable to Kiev. Ukraine isn’t going to give up the 4 oblasts recently annexed by Russia just because it lost Slovyansk.

The only way I can see one side achieve a decisive breakthrough is a scenario where the other launches a wildly overambitious offensive in which it loses a huge share of its manpower and equipment, making it unable to defend against a counter-offensive and resulting in the disintegration of its army.

The main risk for Russia is that, instead of drawing the lessons from its failed invasion last year and attacking in just one direction, it will launch another multiple-front assault and dilute its offensive potential, resulting in heavy losses and the failure to attain their objectives.

Russian tanks that were destroyed on the main road to Kiev during the first days of the war

The main risk for Ukraine is that, to avoid the impression of a stalemate (which is necessary to keep Western aid flowing), it will launch a counter-offensive before it has accumulated enough Western armor, trained its men to use it and built the logistics to support and maintain it. It could also expend so much resources and manpower to defend Bakhmut that it won’t have enough to launch a counteroffensive in the South later this year and take back strategically more important territory.

If one side throws caution to the wind and commits a large share of its manpower and equipment to a wildly overambitious and ill-conceived offensive, only to lose most of them as a result, then I guess the war could end quickly because, as long as the other side was more cautious and retained enough fighting potential, it could exploit this mistake to effectively destroy its opponent’s forces.

In such a scenario, the belligerents wouldn’t necessarily sign a peace treaty, but the losing side would presumably have to sign a ceasefire agreement and the war would effectively be over. However, this scenario strikes me as very unlikely, because I don’t think either side is desperate enough to attempt such a Hail Mary at the moment.

In the case of Ukraine, I think NATO will prevent it from doing something crazy, as they already did last year when, according to The Washington Post, US advisers managed to convince the Ukrainians to abandon their plans for a massive offensive sweeping across the whole South in favor of a less ambitious offensive focused on Kherson.

As for the Russians, they have already lost a lot of men and equipment and can’t afford to suffer the kind of losses they experienced last year again, so I would be surprised if they were not more cautious this year and tried something really crazy that could lead to the disintegration of their army, though I guess that it’s always possible.

It’s starting to look as if their offensive may have already started and, while they are attacking along several axes instead of concentrating their forces in just one direction, they seem to be relatively cautious and apparently haven’t employed their reserves yet, which suggests that when their offensive stalls they’ll still be able to defend.

The scenario of a long but one-sided war ending with a clear victory by one side

While I don’t think that either side has enough men and equipment to achieve a decisive breakthrough and end the war quickly, both have enough to try and I think they will. Russia seems poised to attack first. Ukraine will probably counter-attack in the summer, when it’s ready to deploy the armored vehicles recently committed by NATO members.

Whatever exactly happens, by the time both sides have launched their offensive, they should have lost enough men, equipment and ammunition that another large-scale offensive won’t be possible anytime soon because their offensive potential will have been significantly degraded.

Thus, I think we’re probably looking at several months of what we have seen after Ukraine captured Kherson until Russia started to increase the pressure again, namely relative quiet on most of the front with heavy fighting is limited in time and space and neither side making large gains. The question is therefore what happens next.

Russian tank abandoned in the retreat from Izyum during the Ukrainian counteroffensive in the Kharkiv region last September

One possibility is that one side will keep launching successful offensives that result in substantial gains each time, pausing to reconstitute its offensive potential after each offensive before launching another one, until the other loses the will to fight or no longer believes it will be able to achieve a better outcome through military means and gives up most of its goals to make a deal. Unless one side starts committing far more resources to the war than the other, this would probably take several years, but I guess it’s one way in which the war could end.

A scenario of that sort is what many proponents of Western aid to Ukraine seem to have in mind. They think Ukraine will continue to recover territory and eventually Russia will call it quits, although it’s unclear what they think it will take for Russia to give up or whether Ukraine will take back Crimea.

It’s hard to know what people in the Kremlin think, but judging from some of Putin’s statements, they may also be counting on that kind of scenario, only with the roles of Russia and Ukraine reversed. It’s similarly unclear what they think it would take for Ukraine to agree to terms acceptable to Russia or indeed what such terms would be exactly.

As long as neither side commits significantly more resources than the other, a long war ending in a stalemate is more likely

The problem with that kind of scenario is that it assumes that, after one side has won a battle, the other won’t be able or willing to turn things around by committing more resources to the war and winning the next battle, but that’s pretty dubious.

I guess that if one side manages to defeat the other several times in a row, the latter’s morale will eventually collapse and prevent it from reversing the situation even though it still has the material resources to do so, but as long as we’re not talking about devastating setbacks, and we’re not in the kind of scenario under consideration, it would probably take quite a few defeats to reach that point and there are good reasons to doubt that either side can defeat the other consistently many times without ever experiencing any setback.

As I argued above, drawing from Biddle’s work on the determinants of military power, neither side in this war is likely to achieve the kind of lopsided success on the battlefield achieved by coalition forces during the Gulf War. Any victorious offensive will result in large casualties and equipment losses for the attacking side.

In fact, if the offensive is launched against heavily fortified positions that are adequately supplied and manned (which any strategically significant offensive will be unless again one side throws caution to the wind and squanders ammunition, equipment and men in pointless offensives without keeping enough in reserve to defend against a counter-attack), then the victorious attacking side will actually have lost significantly more ammunition, equipment and men than the defending side.

In the absence of overwhelming superiority in force employment, this should always be true unless the defenders are unable to retreat in good order. However, given the lack of manpower and equipment on both sides, it’s unlikely that either side will be able to perform the kind of large-scale envelopment maneuvers that would prevent that from happening.

Therefore, as long as morale is not critically undermined (which again would likely require several defeats in a row without any success to shore it up), it should require less effort on the losing side’s part to replenish its forces and achieve the mass necessary to successfully defend against the next offensive or even launch its own successful offensive.

Moreover, bureaucratic inertia and political constraints on both sides create a tendency to procrastinate in committing new resources to the war as long as there is no imminent threat (as we have already seen both in the West and in Russia), whereas a setbacks tend to hasten the commitment of additional resources by making the need more obvious.

If this argument is correct, the state of the war can be modeled a bit like a mass on a spring, where any gains in one direction by one side creates the conditions for the other to make gains in the opposite direction next. In that case, we can expect both sides to experience a succession of victories and defeats, until they are exhausted and agree to stop fighting.

The Iran-Iraq war, which lasted 8 years and ended in a draw after each side experienced a succession of defeats and victories that however were never decisive, is a good example of the kind of war to expect in that scenario. A huge difference however is that both Iran and Iraq had fully mobilized their societies toward the war, but as I will explain later, if Russia does that it will not end in a draw.

Iraqi soldiers in Khorramshahr surrendering after the liberation of the city by Iran in 1982

In this scenario the war would in all likelihood also last several years, because as long as neither side achieves a decisive breakthrough, the one that is on the defensive will continue to believe it can turn things around while the other will refuse to make the concessions that would be necessary to reach a negotiated settlement because it will think that victory is within grasp.

It’s impossible to predict exactly how long it would take for the belligerents to call it quits, but as far their negotiating positions are so far apart at the moment and they have already invested so much in the war that I don’t see how it could not take several years. The sunk cost fallacy is one hell of a drug and there is no reason to think that the Russians and the Ukrainians are more immune to it than other people.

In that scenario, there is no reason to think that by the time both sides are ready to stop fighting the front lines will be exactly where they are today (on the contrary they will no doubt have moved), but their strategic position will not have fundamentally changed. I doubt a peace treaty would be signed anytime soon, but there would be a lasting ceasefire because both sides would be exhausted.

After a while, a political settlement may be reached or the war could resume a few years later, but the situation could also turn into a frozen conflict that stays frozen for much longer. I don’t know how the war will end and I’m not confident enough about any scenario to make a prediction, but if I had to bet gun to my head, I would probably bet on a scenario of that sort.

The Biden administration’s plan and why it will probably fail

The scenario of a long but one-sided, at least after a while, war only seems likely if at some point one side is no longer able or willing to commit sufficient resources to turn things around after it has suffered a defeat on the battlefield. In that case, it would become possible and even increasingly easy for the other side to win several victories in a row, resulting to a breakdown of morale and eventually a collapse of the army that would force the losing side to settle even on unfavorable terms.

This would require either a scaling down of the Western commitment to Ukraine or that Russia become unable or unwilling to commit enough resources to keep the war going (alternatively, they could decide to commit the resources but procrastinate too much before doing so, leading to a collapse of their armed forces before that decision could make a difference on the ground), but neither of these possibilities seem very likely in the short or even medium term.

Indeed, by annexing the Donetsk, Kherson, Luhansk and Zaporizhzhia oblasts last September, Putin effectively tied his hands. To be sure, he left himself some wiggle room by not defining precisely the boundaries of the territories to be annexed, but nevertheless he can hardly undo the annexation to make a deal Ukraine could accept without suffering a total loss of face now that he’s done that. He may eventually not have a choice, but given the resources at his disposal, it would probably take several years.

This leaves the possibility that NATO will scale down its commitment to Ukraine’s defense, but I don’t think this will happen anytime soon either. Recently, The Washington Post reported that US officials had warned Ukraine that it had to make the most of what the US was sending this year, because it would probably become more difficult for the administration to secure more aid in the future.

Judging from this New York Times article published a bit earlier, the Biden administration’s calculus seems to be that if the US and its allies make a large effort in favor of Ukraine and send a lot of offensive weapons this year, it will be able to launch a successful counteroffensive in the South that will cut the Russian land bridge.

Ukraine will then be a position to threaten Crimea, which US officials think will force Putin to the negotiating table, where the Ukrainians can use Crimea as a bargaining chip to get the best deal possible. This will end the war and will prevent the US from getting bogged down in Ukraine and having to send large amount of military assistance for years.

If that’s in fact the administration’s plan, I think it’s extremely unlikely to work. First, I don’t believe that Ukraine can realistically cut the land bridge to Crimea, where the Russians are dug in and have built strong defensive positions, with a counteroffensive this year. But even if the Ukrainian armed forces somehow managed to pull it off and took back Melitopol, contrary to what US officials apparently expect, I don’t think it would result in a negotiated settlement.

Indeed, this plan doesn’t just assume that Ukraine’s counteroffensive will be extremely successful (more than I think is realistic), but also that both Ukraine and Russia will be prepared to negotiate seriously after this year’s offensives are over. But it seems very unlikely that either of them, let alone both, will be ready to make the kind of compromises that would be necessary to make a deal possible then.

In the case of Ukraine, one might think that since it’s dependent on the West to stay in the fight (anyone who doubts that should look at the data on the production of shells), the US could force it to give up the goal of taking back Crimea by threatening to reduce the economic and military aid. However, for this to have a chance of working, the threat would have to be credible.

If the Ukrainians don’t believe that Biden would go through with it, they will simply ignore it or more probably attach so many conditions that Putin will not take the offer seriously, but I think they have very good reasons to think that Biden would not go through with the threat.

Indeed, after a period of hesitation, the US and NATO have now committed themselves publicly to Ukraine’s defense in very strong terms. While they have avoided tying their hands by saying anything specific about what kind of deal they would regard as acceptable, US and NATO officials have repeated claimed that Washington and its allies would never abandon Ukraine.

If Ukraine were defeated and forced to sign a peace settlement on terms dictated by Russia but NATO had never made such a commitment, it would have been one thing, but now that it has its credibility is on the line and that outcome would damage it very badly. It wouldn’t matter if that were because Kiev refused to compromise on Crimea.

Now, if the West scaled down its assistance no matter the reason, this is almost certainly what would happen. Ukrainian officials understand that and therefore I don’t think they would regard a threat to reduce support as credible.

Thus, given how determined Ukrainian officials seem to be to take back Crimea and how difficult it would be politically for Zelensky to renounce a goal that is overwhelmingly supported by the population and that he has repeatedly endorsed in the most unambiguous terms, I think it’s extremely likely that they would take the risk and call his bluff.

Zelensky has repeatedly pledged that Ukraine would take back Crimea

One the other hand, if as I expect the Ukrainians don’t manage to cut the Russian land bridge, then it may be easier to persuade them to give up the goal of taking back Crimea, but it won’t matter since they won’t be in a position to threaten Crimea anyway and therefore Moscow will not have the reason posited by the US administration’s plan to scale back its goals to protect its hold on the peninsula.

If the Ukrainian armed forces managed to cut the Russian land bridge and the US convinced Kiev to give up the goal of taking back Crimea, then Russia might indeed be induced to scale back its ambitions and make a deal that is acceptable to Ukraine, but even that is hardly obvious since it would result in a huge loss of face for Russia and especially for Putin just one year after he declared the annexation of 4 Ukrainian oblasts, so the temptation to double down instead would be strong and I doubt he’d resist it. Once again the sunk cost fallacy is one hell of a drug.

Still, now that it has committed itself so strongly to Ukraine’s defense, the US doesn’t have any very good options and this may be the best plan it has. Washington could increase the probability that Ukraine’s counteroffensive will be successful enough to induce Russia to make a deal by sending more equipment, again I don’t think the amount of military assistance promised by the US and its allies will be sufficient and arrive quickly enough, but this would probably reduce the probability that Ukraine would agree to use Crimea as a bargaining chip, so it’s in a catch-22.

Nevertheless, now that NATO’s credibility is on the line, I don’t believe that the US and its allies will significantly reduce the amount of economic and military aid they are sending to Ukraine if, as I predict, Ukraine is unable to achieve a decisive breakthrough this year despite the recent influx of Western military assistance.

That’s because I also don’t expect Russia to back down and I don’t believe that NATO will just watch it defeat Ukraine without doing anything. This may well happen eventually, because sooner or later someone is bound to blink, but I don’t think anyone will anytime soon.

Biden was just in Kiev where he made a surprise visit, declared that he thought “it was critical that there not be any doubt, none whatsoever, about US support for Ukraine in the war” and pledged his government’s “unwavering support for the nation’s independence, sovereignty and territorial integrity”.

It’s going to be hard to scale down the American commitment to Ukraine after that, even if the Democrats lose the White House in 2024, because the national security apparatus will insist to whoever replaces Biden in that scenario that the US credibility is now at stake.

In the meantime, I find the notion that Republicans, who recently took back the House of Representatives, will cut assistance to Ukraine completely unrealistic. Republicans in Congress will make a show of criticizing Biden’s policy on Ukraine to pander to their base, which is increasingly opposed to support for Ukraine (though I think they don’t care about it much yet relative to other issues like inflation), but in the end they will give him what he asks for because in reality most of them are probably more hawkish than Biden on Russia.

If there is a recession, then it’s a different story and Ukraine will be in trouble, because then it will become much harder for Western political leaders to justify sending billions of aid to Kiev every year. Nevertheless, as I will explain shortly, I think now that NATO has committed itself publicly to Ukraine’s defense it will take a lot for Western leaders to leave Kiev in the lurch.

If they have to, they will probably start by reducing economic aid to protect military assistance, which is more critical. Eventually, this would probably lead to a Ukrainian default, which in turn would require financing the deficit through money printing. This would generate a lot of inflation and badly damage civilian morale, which eventually would affect morale on the front. However, it increasingly looks as though there won’t be a recession this year, so this is probably not a problem Ukraine will have to face soon.

It’s more likely that either the West or Russia will procrastinate too much before making the decision to commit the necessary resources, both have already shown a disposition to do so, but since as long as they are about equally matched in terms of resources neither side is likely to win battles without suffering heavy losses, I doubt that procrastination will ever be fatal until one side commits so much resources than the other can no longer match its effort. However, in that case, the inability to match the other side’s effort and not procrastination will be the issue.

Credibility and the logic of escalation

But while neither side is likely to back down anytime soon, they also can’t keep this up forever, though not for the same reasons. Due to increased spending and decreased revenue, Russia now faces a large budget deficit. While it can probably finance this deficit with the reserves it still has access and increased domestic borrowing for 2 or 3 years if the situation doesn’t get worse, it probably will get worse and this means that it will have to raise taxes and reduce public investments, thereby undermining future growth.

If the war lasts significantly longer than that, which I think is likely, it will eventually have to reduce social spending even if at the moment they are legally protected from cuts and the government will probably wait until it has no other choice to do that. It will take a while, but eventually the situation will become very difficult, especially if the budgetary demands of the war increase.

As for the West, while the war doesn’t impose serious budgetary constraints yet and is unlikely to do so anytime soon, the sums allocated to Ukraine are starting to be large enough that if the war goes on for years they will become politically hard to justify, especially if there is a recession which is bound to happen eventually.

The real economic cost of the war for the West, especially for European countries, is the increase in energy prices caused by the Russian gas cutoff. However, since I doubt that European countries will ever buy large quantities of Russian natural gas again, this is probably sunk cost for the most part.

What is much more problematic is that assistance to Ukraine is emptying Western military inventories and putting their military production capacities under a lot of stress. This is causing a lot of anxiety in the military establishment of Western countries because they don’t want to be exposed in case of contingency.

This is particularly true in the US, which has other commitments in the rest of the world and has to maintain sufficient inventories in case they are needed elsewhere. Right now, as a result of the war, US inventories are extremely low for several critical systems and it will take years to replenish them at the current rate of production. The recently announced increase in production capacity for artillery shells will be enough to prevent Ukraine from collapsing, but not to replenish US inventories quickly.

In fact, Washington has been trying to pivot from Europe to Asia for years and is much more concerned by China than Russia, because Russia isn’t a serious competitor for the US whereas China is. Supporting Ukraine is a vital interest for Poland and other NATO members in Central and Eastern Europe, because they want to preserve Ukraine as a viable buffer against Russia, but the same thing can’t be said for the US and Washington’s main reason for responding so forcefully to Russia’s invasion is probably to keep the Alliance together.

Although many people in Washington’s foreign policy establishment want to bleed Russia in Ukraine for ideological reasons, Biden and Sullivan, his National Security Adviser, seem eager to end the war so they can resume the pivot to Asia.

The fact that both sides can’t back down but also can’t keep this up forever potentially sets the stage a very dangerous situation. Indeed, it creates a strong incentive on both sides to launch another round of escalation and commit more resources to the war every time it seems not to be going anywhere, in the hope that it will break the stalemate and end the war by forcing the other side to compromise. However, since for reasons I have already explained neither side can easily back down, rather than compromise, the other side is more likely to reply in kind by allocating more resources to the war.

The dual requirement of not losing face and not keeping the war going forever can thus result in a cycle of escalation that is a classic example of a collective action problem. Indeed, due to the gradual nature of the process and the importance that states attach to maintaining their credibility, each side will end up paying a cost such that, had it known in advance that it’s what it would take to achieve its goals, it would have rather changed them and would never have started down that slippery slope in the first place.

In this respect, the current situation is similar to what happened when NATO intervened against Serbia over Kosovo in 1999, but far more dangerous. When that intervention started, Western leaders thought that Milosevic would cave quickly and that it would be over in a few days. But Milosevic didn’t cave, the intervention dragged on and eventually it started to look as though a ground invasion would be necessary to force him to do so.

A man standing in front of wreckage after a NATO strike missed its target and destroyed apartment buildings during the Kosovo War in 1999

Now, if you had told Western leaders before the bombing started that a ground invasion would eventually be necessary, they would probably never have intervened, but once they had they couldn’t back down anymore because NATO’s credibility was now on the line.

Fortunately, Russia eventually stopped brooding and joined the West’s effort to pressure Milosevic into giving up (Russia opposed the intervention and was incensed when NATO started to bomb Serbia without the Security Council’s authorization), who relented because he was now isolated and NATO’s bombing campaign was intensifying.

Of course, Russia’s commitment to Serbia was not anywhere near the West’s commitment to Ukraine and other than threatening to use nuclear weapons there was nothing it could do to stop NATO’s intervention because it was extremely weak, whereas the West still has plenty of room to escalate its support.

But what happened during this episode nevertheless illustrates how, once states have put their credibility on the line, they can become willing to incur a much greater cost to achieve their goals than they would originally have been prepared to pay.

This is probably already the case with the Russo-Ukrainian war. Since it started, there has already been a gradual escalation resulting in a significant increase of the resources that both sides have committed to the conflict, especially with Russia’s mobilization in September and the West’s recent influx of military assistance to Ukraine.

It’s extremely unlikely that Russia, which apparently expected little resistance from Ukraine and a much more muted Western reaction, would have invaded in the first place had it known that it would end up being so costly.

Similarly, other than Central and Eastern European countries, I’m not sure that the US and its allies would have committed themselves to Ukraine’s defense. Indeed, they initially expected the Ukrainian government to collapse and were planning to support a long insurgency, which would have been much less costly and wouldn’t have been such a drain on their military inventories.

The scenario of a runaway escalation ending with a decisive Russian or Ukrainian victory

If I’m right that neither Ukraine nor Russia will be able to wrap this up quickly, the question is where does this process stop. This is very difficult to predict, because ultimately it depends on how committed to achieving their goals each side is and on how the war unfolds from now on, which is hard to know.

It’s possible that eventually both sides will reach some kind of equilibrium, where they no longer try to force a decision by increasing the amount of resources they commit to the war (because they are not able or willing to do so), but rather keep their effort constant and hope that the other side will tire of it first.

Eventually, one side and probably both would indeed relent, revise their goals downward and a deal would be struck to end the war on conditions that neither side would consider acceptable right now. This is the scenario I sketched above of a long war in which both sides alternate victories and defeats without ever achieving the destruction of their enemy’s fighting potential. As I said above, if I had to bet, I would bet on that scenario.

The other possibility is that of a runaway escalation, where the amount of resources both sides commit to the war doesn’t tapper off, but instead each side keeps ramping up its commitment until one of them is no longer able or willing to follow the other and, depending on who that is, either Ukraine or Russia wins a decisive victory.

The only scenario of that sort I can think of where Ukraine wins decisively is one in which the West keeps increasing the amount of assistance it gives to Kiev, Putin tries to match the West’s effort and this results in some kind of revolution or coup that completely disorganizes the country.

It could happen but I think it’s very unlikely, because if at some point he feels that Russian society or the elites won’t tolerate another round of escalation, Putin will back down and the West will lean on Ukraine to make a deal that doesn’t imply a total humiliation for Russia rather than risk that a desperate Putin orders the use of nuclear weapons to prevent it or that a revolution plunges the country into chaos.

Indeed, while some people on the Internat who suffer from Russia derangement syndrome may fantasize about that, the prospect of a collapse of the central government in a country with the largest nuclear arsenal in the world and a vast conventional arsenal would be a nightmare and the West would do everything to avoid it. This was true in 1991 when Bush made his infamous “chicken Kiev” speech and it would still be true today.

It should be easier for the West to convince Kiev to give up the goal of taking back Crimea by the time such a situation arises, because if this ever happens it will presumably take a long time so the Ukrainians will be exhausted by years of war and should be more eager to end it, while the West will have incurred a huge cost to help it and that should make it more willing to lean hard on Ukraine to make a deal.

On the other hand, if Russia keeps increasing the amount of resources it commits to the war and it doesn’t cause a revolution or a coup, the West will eventually stop trying to match Moscow’s effort and will start pressuring Kiev to compromise while it still has some leverage.

This could happen before things get really out of hand, especially if there is a recession in the West or if China decides to sell military equipment to Russia, but if the logic of escalation continues to play out for long enough we could end up with a scenario in which Moscow reaches Cold War levels of military spending, at which point there would be nothing the West could do to prevent Ukraine from losing and Putin from dictating the post-war settlement.

Indeed, while the US and its allies have a combined GDP that is almost 20 times larger than Russia, GDP doesn’t magically translate into resources for Ukraine. Those resources have to be actually committed and, if Russia eventually allocates 20%-25% of its GDP to the war in Ukraine, each NATO member would have to spend between 1% and 1.5% of its GDP to support Ukraine to match that effort and that is never going to happen.

A few Central and Eastern European NATO members, Poland and the Baltic republics, would probably be willing to do it if they had to, but the rest of the Alliance and certainly the most powerful members never will. In particular, the US isn’t going to spend $250 billion a year just on military assistance to Ukraine and leave itself completely exposed to a Chinese move in the Indo-Pacific region, which such a commitment to Ukraine would invite.

But while I think such a scenario is more likely than one in which Putin induces a revolution or a coup by trying to launch another round of escalation in Ukraine, I still think it’s very unlikely, precisely because trying to reach that level of spending on the war might cause a revolution or a coup so he will be reluctant to try. The reason has to do with the nature of Putin’s regime and I think is not well understood by most commentators.

His regime is a personal autocracy and, as Timothy Frye explained in a recent book, this means that it shares the weaknesses of this type of regime and that paradoxically it makes Putin a weak leader. In a personal autocracy, the autocrat is wary of relying too much on any particular groups or individuals to govern, including the population.

This safeguards his hold on power, because it means that neither the population nor any particular institution or group of people can remove him, but it also makes him weaker because he always has to maintain a delicate balance between them and state capacity requires that the leader be able to empower and trust groups and institutions to implement his policies.

In that respect, Russia is very different from the Soviet Union and other totalitarian states, which had a very well-developed infrastructure to mobilize the population toward the state's goals and powerful institutions to implement the leadership’s policies.

Setting up a real war economy and extracting Russia’s still considerable resources to direct them toward the war effort would require a degree of popular mobilization unprecedented under Putin and would also make people in the military and technocrats in the economic ministries very powerful.

This would break the delicate balance on which Putin’s regime currently rests and in effect turn it into a completely different animal, which seems unlikely to happen not only because such a transformation would not be easy but also because it would be very risky for Putin.

Nevertheless, however unlikely it may seem now and again I don’t deny that at the moment it seems very unlikely, I don’t think that possibility should be dismissed because it could still happen. One could even imagine that a coup will take place in Moscow, but that instead of resulting in the end of the war, hardliners committed to defeating Ukraine will replace the current leadership and gradually put in place a regime that can achieve the degree of mobilization necessary to achieve that goal, although this is even more speculative.

Like Putin a year ago, Saddam also thought the war would be short when he invaded Iran in 1980, but he was wrong. By 1982, Iran had recovered most of the territory initially conquered by Iraq, which now had to fight to protect its own territory. While it was very different in some respects, Saddam’s regime nevertheless shared many of the same weaknesses as Putin’s and I don’t think many people would have bet at the time that, a few years later, Iraq would spend more than 50% of its GDP on the war effort.

The Swords Of Qadisiyah in Baghdad, a monument built after the Iran-Iraq War to commemorate what Saddam’s propaganda considered a victory

Yet it’s still what happened and this required a significant transformation of the regime. For instance, it’s during the war that cult of personality developed around Saddam, which the regime used as a tool to mobilize society toward the war effort. Again, such a transformation of Putin’s regime seems very unlikely at the moment, but my point is that if the war lasts several years it’s very difficult to predict what could happen and such a scenario can’t be dismissed.

Similarly, while I expect the Russian armed forces to be in pretty bad shape at the end of the year, we should not conclude that it will never recover because with enough time and resources it could happen. The Iraqi army, which in 1982 was exhausted and incapable of any offensive action, was completely transformed by the end of the war and had become a far more effective instrument capable of combined arms operations.

In the case of the armed forces, such a transformation would arguably be more difficult for Russia. Indeed, Iraq was only able to achieve it because it could procure modern equipment abroad, whereas Russia mostly can’t.

Of course, Iraq didn’t have a military industry to speak of, whereas Russia has one of the largest in the world. But it relies a lot on Western parts that have become much harder to source for Russia due to sanctions, so it would have to substitute them with Chinese or domestic parts, which has proven largely unsuccessful in the past.

Nevertheless, necessity is the mother of invention and if the war lasts years we can’t rule out that eventually Russia would pull it off, just as we can’t rule out that Putin’s regime would gradually undergo the kind of transformation required to mobilize society for war and achieve Cold War levels of military spending. Saddam eventually did it, though he was greatly helped by the fact that after 1982 Iraq was fighting to defend its own territory, so we should not assume that Putin never will.

The difference is that Iraq had a much smaller population and GDP than Iran, so despite the fact that by the end it was waging a total war, it was only able to fight Iran to a draw because it had a lot of external support whereas Iran had very little. Russia on the other hand has a pre-war population more than 3 times as large as Ukraine and a GDP now more than 10 times larger.

Of course, Ukraine has a lot more support than Iraq, but as I noted above there are limits to how much aid the West can give and if Russia ever reaches Cold War levels of military spending it won’t matter. The Ukrainian armed forces will eventually be crushed and, when this happens, the Ukrainians will have no other choice but to resort to asymmetric warfare if they want to keep fighting.

However, since in such a scenario Ukraine would have already been fighting a conventional war for several years by the time its armed forces can no longer fight, I doubt it will launch a large-scale insurgency and think it’s more likely that Kiev would make a deal. Just because this scenario is unlikely and we find it unpleasant doesn’t mean that we should dismiss it out of hand. The war could also end that way.

Conclusion

Everything I say in this essay should be treated with extreme caution. First, while I have tried to catch up on military matters since the war started, I’m no military expert and, unlike with other topics on which I also have no credentials but where I’m very confident that I’m not missing anything important, I wouldn’t bet that it’s the case here.

Moreover, while I have been diligent in collecting and analyzing the publicly available data, those data are extremely partial and this inevitably adds to the uncertainty. Finally, war is a very uncertain process that is intrinsically very difficult to predict, so even someone who is better versed in military matters than me and has access to better data should only approach the question with a lot of humility.

Thus, I have avoided making a firm prediction about how the war will end in this essay, because I think it’s impossible to make such a prediction with even moderate confidence. Instead, I have examined a range of possible scenarios and I have only tried to give a vague assessment of how likely each of them seems to me, which is less ambitious but also more realistic and still a useful exercise in my opinion.

Of course, I could not consider all the possible scenarios, because there are practically infinitely many. So I focused on a handful of types of scenarios, each of which could be instantiated by many different specific scenarios depending on how the details are filled in, that I consider the most plausible and ignored the rest.

In particular, one omission deserves to be noted, lest it be misinterpreted. Many people will probably be surprised that I did not discuss the possibility that Russia will eventually use nuclear weapons. This is because I think it’s very unlikely and, while people disagree about how unlikely it is exactly, virtually everyone agrees with that.

To be sure, I did examine other scenarios that I also consider very improbable, such as the scenario of a Ukrainian victory by the end of the year, but that’s because many people disagree and think they are plausible, whereas almost everyone seems to agree that a nuclear escalation is very unlikely and disagreements center on how this low-probability possibility should affect decision-making.

To be clear, if I didn’t discuss such a scenario it’s not because I think that the possibility of a nuclear escalation is irrelevant and should not affect policy, on the contrary. While such a scenario is very unlikely, it would also be extremely dangerous, so I think it should be taken very seriously and that people are wrong to dismiss that possibility as irrelevant.

But it raises a number of complicated philosophical questions, such as how assignments of probability to non-repeatable events can be meaningful and how very low probability events with disastrous consequences should affect decision-making, so I think it should be treated separately.

Based on the analysis presented above, I think the most likely scenario is that of a long war that lasts several years and ends in a stalemate when both sides are exhausted, but other scenarios can’t be ruled out. In particular, we can’t rule out the scenario of a runaway escalation in which Russia would eventually reach Cold War levels of military spending, at which point there would be nothing the West could do to save Ukraine from defeat.

Should this scenario come to pass, by publicly committing to Ukraine’s defense and putting its credibility on the line, NATO would have walked itself into a trap by becoming a prisoner of the logic of escalation, only to produce exactly the result it feared the most.

Indeed, in helping Ukraine, NATO’s main goal is to durably weaken Russia and prevent it from turning Ukraine into a satellite that can no longer act as a buffer protecting the Alliance’s eastern flank. However, if Russia eventually reaches Cold War levels of military spending, not only will it defeat Ukraine but it will be armed to the teeth and Ukraine will no longer be able to act as a buffer with NATO. However unlikely that possibility may be, it’s worth thinking about it.

Finally, it should also be noted that, in every scenario I consider plausible, the war last several years and this has dramatic consequences for Ukraine. Indeed, it means that in addition to being physically destroyed, it will almost certainly undergo a demographic collapse from which it won’t be able to recover this century.

To be sure, Russia will also come out of this war considerably weakened economically for decades to come no matter how it ends exactly and this will have bad demographic consequences, but it won’t be much of a consolation to Ukraine and I don’t think people realize the extent of the catastrophe Ukraine is facing even if from a purely militarily point of view it ends up winning.

What implications this analysis has for policy is a complicated question, not least because it depends on what the interest of NATO and the different members within it are, so I will discuss that some other time. In the meantime, my hope is that, even if you disagree with my conclusions, this essay will make you think about how the war could end and how the West’s policy could affect the answer to that question.

ADDENDUM: When I argue that if Russia somehow managed to reach Cold War levels of military spending, I’m implicitly assuming that Russia and NATO get approximately the same amount of bang for their buck. Of course, this is almost certainly not true, but I also think it's really difficult to predict exactly how that would play out. Moreover, there is no reason to assume it would play out in the same way at different level of commitment (i. e. the elasticity of military power is not the same depending the amount of resources committed), so I think it’s probably best to make that assumption for that kind of analysis even if again we have every reason to think it's not strictly speaking true. Indeed, since it’s so difficult to predict how military power would respond to a change in the amount of resources committed to the war, trying to make a more realistic assumption on that point would probably just invite bias and prejudice to play a larger role in the analysis. The figures I give in the passage in question should therefore not be taken too seriously, but I think the general conclusion is correct, even if we can squabble about the exact figures.