Ending the War in Ukraine: Analysis and Recommendations

Reaching a peace deal in Ukraine is not impossible, but it will require many Western leaders to recalibrate their expectations.

[Photo Credit: By Kyivcity.gov.ua, CC BY 4.0]

The war in Ukraine is nearing the end of its third year, but as yet there is no indication of imminent peace. For the past three years, Western powers, led by the United States of America, have sought a solution to the war by means of a single strategy: supporting Ukraine and pressuring Russia. The aim has been peace through victory. This strategy has failed. Probably over 200,000 Russian and Ukrainian soldiers have been killed; possibly tens of thousands of civilians have been killed also; and property worth tens of billions of dollars has been destroyed. The time has come when the policy of peace through victory needs to be replaced by a policy of peace, pure and simple.

The return of Donald Trump to the US presidency in January 2025 offers an opportunity to pursue such a policy. President Joe Biden has shown no interest in mediating a peace process. Neither have any European leaders. Trump, however, has indicated that he wishes to do so, and as a first step has appointed General Keith Kellogg as his Special Envoy for Russia and Ukraine, tasked specifically with finding a way to end the war.

In this context, proposals for how to end the war in Ukraine have acquired a new importance. Unfortunately, to date, many such proposals have been divorced from any understanding of how in practice wars actually end. This paper thus seeks to ground policy recommendations in studies of war termination. To that purpose, it first analyzes war termination theories and then applies those theories to the war in Ukraine.

The paper examines the topic from the standpoint of what is most likely to produce a lasting peace settlement. The rights and wrongs of the Ukrainian and Russian causes are not the subject of concern. While it has been said that “there is no peace without justice,” it might be more correct to say that “there is no justice without peace.” The aim of the analysis is peace in the negative sense of an absence of war, not peace in the positive sense, as the achievement of justice. Some may object to this approach, but any peace plan that fails to place the ending of war at the top of its agenda is liable to fail.

How Wars End

The starting point for any realistic proposal to end the war in Ukraine must be an understanding of the conditions that are necessary for successful war termination, as well as of the barriers that prevent political leaders from recognizing that those conditions are present.

There are many variations of war termination, but in essence they boil down to two options:

1. The absolute victory of one side, allowing it to impose its terms on the other. In this case, the war ends because one of the warring parties ceases the struggle. This could be due to its complete destruction or disintegration (e.g. the Iraqi army in 2003), its withdrawal (e.g. the US withdrawals from Vietnam and Afghanistan), or its surrender (e.g. Germany and Japan in World War Two).

2. Neither side achieves absolute victory, and the war ends through a negotiated settlement that involves some degree of compromise by both parties. This need not mean that both sides do equally well in the final settlement: one may do decidedly better than the other. The form of the settlement may also vary. In some instances, it may take the form of a peace treaty. In other instances, it may consist of a ceasefire without any treaty (the Korean War being an example). Regardless, the key feature is that the settlement is negotiated not imposed.

In the first case, wars end when the losing side is either destroyed or gives up. Thus it has been said that “War is pressed by the victor, but peace is made by the vanquished¹.

The second case is more complicated. According to a popular thesis developed by William Zartman, wars end when both warring parties perceive themselves to be in a “mutually hurting stalemate,” and when they both perceive the possibility of a way out via a negotiated settlement. At such point, the conflict is deemed to be “ripe” for termination². The term “mutually hurting stalemate” is somewhat misleading, as it does not imply total deadlock; one side may hold a definite advantage over the other. However, it does imply that neither side believes itself to be able to achieve absolute victory, and it does imply that both sides perceive the existing situation to be harmful to their interests.

Objective criteria, such as success or failure on the battlefield, play into both these scenarios. However, what matters is not objective reality but rather the warring parties’ perceptions of reality³. In the first case, wars end because one side either perceives the war not to be worth continuing or perceives itself to have lost. And in the second case, wars end because both sides perceive that there is a mutually hurting stalemate and that there is possible negotiated way out. Bringing a war to an end is thus a question of altering perceptions. In the first case, it involves convincing the losing side that defeat is inevitable; in the second case it involves convincing both sides that victory is impossible.

Needless to say, this is easier said than done. Even if it is clear to an objective outside observer that one side has lost or that neither side is capable of absolute victory, those involved in the fighting may not view things the same way or may be unwilling to act on the knowledge. There are a number of explanations for this:

1. Cognitive biases: Political and military leaders, like all human beings, are subject to cognitive biases that prevent them from correctly assessing their situation. Optimism bias, sunk cost fallacies, the tendency to take risks rather than accept bad certainties, and so on, mean that wars generally continue long beyond the point when a purely rational actor with perfect knowledge would have brought them to a halt⁴.

2. Internal political and bureaucratic dynamics: Political leaders may be fed overly positive information by subordinates; they may be fearful of the political consequences of accepting defeat; or they may meet resistance from powerful forces who wish to continue the war. The attitudes of the general public, the political elite, and the military leadership all play into this dynamic⁵.

3. Imperfect information. War may be seen as a method by which involved parties exchange information about their relative strength and resolve. But as the great Prussian strategist Karl von Clausewitz pointed out, war is shrouded in uncertainty. Even if one has good information about the state of one’s war effort (which is not always the case), information about the state of the enemy’s is always limited. Future developments are also unpredictable. For instance, one cannot know for sure what one’s allies will do. Humans also tend to be less able to recognize change if it happens slowly than if it happens rapidly. Political and military leaders may not recognize their relative military decline until long after it has become critical if the decline is gradual, not due to a sudden and unexpected defeat. One study thus concludes that “combat is a relatively inefficient means of hastening war termination through information transmission.”⁶

4. Distrust (often referred to in academic literature as the “commitment credibility” problem). Even if leaders recognize that they have lost or are stalemated, they may be unwilling to negotiate because they do not trust their opponents to comply with the terms of any agreement – i.e. they do not believe that their enemy’s commitments are credible. Perceptions of past behavior are crucial in this regard⁷. If one’s enemies are seen to have broken agreements in the past, one will be reluctant to make new agreements with them, however bad one’s position. In extreme cases, fears of non-compliance can induce warring parties to continue to insist on absolute victory even in the face of obvious battlefield defeat⁸.

5. Spoilers. Efforts to make peace may be deliberately sabotaged either by individuals or groups within a state, or by third parties⁹.

The analysis above suggests that third-party state leaders who are seeking to end a war being fought by other states have two options:

1. Alter the perceptions of one side to convince it that it has lost and must concede. In this instance, it is obviously easier and quicker to alter the perceptions of the side that is in a weaker position. Trying to convince the stronger side that it is losing will likely be very difficult and only possible after a very long process which would involve so altering the dynamics of the war that the relative positions of the two warring parties are reversed.

2. Alter the perceptions of both sides to convince them a) that neither of them can win an absolute victory, b) that the current situation is harmful to their interests, and c) that there is plausible way out via negotiations. Given the problems noted above, this too is likely to be a slow process.

The quickest way to end a war is thus probably to work on convincing the weaker side that its cause is lost and that it must settle. The second quickest way is option 2 above. And the slowest is to try and alter the perceptions of the winning side in order to convince it that it is losing.

Political leaders whom one is trying to convince in this way will probably be loath to admit that their war will end in a suboptimal way. Peacemakers will have to overcome the barriers to recognizing reality mentioned above. To this end, one may offer the following possible courses of action:

1. Alter reality to conform with the desired outcome. This would involve exerting pressure on one side so as to weaken it, while aiding the other side so as to strengthen it. In accordance with the logic above, this is more likely to succeed, and more likely to have rapid effects, if it involves pressuring the weaker side and/or supporting the stronger side. This approach has a number of weaknesses, however:

• Given the uncertainties of war one cannot be certain that the combination of pressure and support will have the desired impact on objective reality;

• Even if it does, one cannot be certain that the perceptions of the warring parties will alter accordingly, especially (as is likely) if the change in objective reality is gradual; and

• Even if perceptions are suitably altered, one cannot be sure that the parties will respond in the desired manner due to the issue of distrust mentioned earlier.

2. Work to overcome the targeted state’s cognitive biases and the problem of insufficient information. The weaker party may not, for instance, recognize its position due to optimism bias or because it misunderstands the level of support it may receive in the future from allies. Frank conversations that disabuse state leaders of their illusions may be necessary.

3. Enable state leaders to overcome internal political opposition to a settlement of the war. This could be done, for instance, by promises of financial aid after the war, or by very overt arm-twisting that makes it clear to internal forces opposed to peace that their leader has been left with no other choice by key outside actors.

4. Devise the settlement in such a way as to reassure the warring parties that their opponents are likely to abide by the commitments they have made. In this regard, a formal peace treaty is preferable to a pure ceasefire, as the latter involves almost no commitments beyond ceasing military actions. In addition, the more contested issues that can be resolved in any peace treaty and not left hanging till later, the better. Security guarantees, the deployment of peacekeeping forces, and other similar devices may also help overcome problems of mutual distrust.

5. Engage with potential spoilers to convince them that it is not in their interest to sabotage negotiations. A combination of positive and negative inducements may be used to persuade them to adopt a more amenable position.

The War in Ukraine

The trajectory of the war in Ukraine has surprised all observers. One would be very hard put to find a single analyst who has correctly predicted all its ups and downs. War is inherently uncertain, and given this record, one would be rash to declare that one knows the likely future direction of the conflict. Nonetheless, after nearly three years of fighting certain things have now become sufficiently clear that one can draw fairly confident conclusions about some key issues.

First, it is now obvious that Russia is the stronger of the two parties. Moreover, its relative strength is growing. While one cannot rule out a reversal of the trend in Russia’s favor, it stretches plausibility to imagine that such a reversal could go so far as to render Ukraine stronger than Russia. The issue is more the extent of Russia’s future advantage than the existence of such an advantage.

Russia’s military superiority can be measured in many ways. The first is in terms of territorial gains. These have accelerated in recent months, with Russia capturing 725 square kilometers of Ukrainian territory in November 2024, the largest amount since the first weeks of the war in early 2022¹⁰. The second is military production; Russia’s production of weaponry far exceeds that of Ukraine, and in key sectors, such as artillery shell and armored vehicle production, it exceeds that of all Ukraine’s Western allies put together. A recent German report noted, for instance, that “Production has strongly increased across all weapon systems,” with Russia producing sufficient weaponry not only to replace its losses but also to outfit new formations¹¹. A third area is manpower. Russia began the war in February 2024 with an invasion force of at most 200,000 soldiers. By early 2023, the size of the Russian army in Ukraine had increased to around 360,000 men, and by early 2024 to about 470,00¹². According to Vladimir Putin, in June 2024 the number of Russian troops in the zone of military operations was just under 700,000¹³. Despite claims of massive losses, the Russian army in Ukraine has grown considerably in size.

Ukraine, by contrast, is experiencing severe difficulties. Not only is it inexorably losing ground, but it has little prospect of turning the situation around in its favor due to a) the extreme unlikelihood that Western support will increase substantially beyond its current level, b) manpower shortages, and c) growing problems of morale. The latest mobilization effort has not yielded the desired results, while desertion is become ever more prevalent. According to recent reports, over 100,000 Ukrainian soldiers have been charged with desertion during the war, of which some two-thirds were in 2024 alone. Recently Ukraine is estimated to have lost about 4,000 soldiers a month more than it has been able to recruit¹⁴. While the Russian army is growing larger, the Ukrainian army is growing smaller.

Protracted wars necessarily become wars of attrition and of morale. At present, Russia is winning in terms of attrition, while it also appears that Russian morale is holding up better than that of Ukraine. There is no obvious reason to suspect that either factor will change significantly in Ukraine’s favor in the short to medium term.

From this one can draw the conclusion that an absolute Ukrainian victory (measured in the terms set by the Ukrainian government itself – which is to say the recapture of all its lost territory) is almost impossible. That does not mean, however, that Russia is assured of victory in the sense of acquiring such a dominant position that it can force whatever terms it wishes on Ukraine. Such an outcome remains possible, should, for instance, Western aid to Ukraine entirely cease or should Ukrainian morale collapse. Absent that, however, Russia’s current advantage is not so great as to make such a result probable. Russia is advancing, but only slowly, and it has not demonstrated that it has the capacity to exploit any breaches it makes in the Ukrainian lines in such a way as to permit rapid advances over large distances. At the current rate, it will take Russia at least another 12 months just to capture the rest of Donetsk province. Ukraine’s capacity to resist and inflict heavy casualties on the Russians remains large. Moreover, much of Russia’s military production involves refitting old Soviet equipment. As stockpiles run down, production may begin to run down too, leading some commentators to believe that Russia’s military strength may peak in 2025.

Given this, Russia is not currently well placed to inflict such a massive military defeat on Ukraine as to force it entirely to submit. Objective reality, therefore, points towards a situation of mutually hurting stalemate, rather than absolute victory, albeit a stalemate which is hurting Ukraine far more than it is hurting Russia.

The question which then arises is whether the leadership of Russia and Ukraine correctly perceive this reality, and if they do, whether they are likely to act on this perception. The fact that the war continues, and that negotiations between the two are not even taking place, suggests that the answers to these questions are no. At the start of December 2024, Russian presidential spokesman Dmitry Peskov declared that he saw “no grounds for negotiations yet.¹⁵” Russian officials continue to insist on their original demands – Ukrainian neutrality, demilitarization, and de-Nazification – to which they have now added recognition of the “new territorial realities,” in other words recognition of Russian control over those Ukrainian territories it has annexed. As yet, there is no sign of any flexibility that might indicate an understanding that the Russian army is not in a position to so weaken Ukraine as to be able to impose these terms by force.

Ukrainian leader Volodymyr Zelensky, by contrast, has recently demonstrated a tiny bit of flexibility, but arguably only a tiny bit. In late November 2024, he suggested that Ukraine would not be able to recapture “some” territory by force, notably Crimea, and stated that he would be willing to freeze the conflict and de facto abandon efforts to retake territory in return for NATO membership¹⁶. But the reference to “some” territory suggested also a continuing belief that other territory could be retaken by military means, while the request for NATO membership for all of Ukraine within its pre-2014 borders is hardly realistic. It is not obvious that Zelensky has yet come to terms with the reality of his situation.

Neither side, therefore, despite their decidedly limited military prospects, and the heavy losses they are suffering, at present acknowledges that the costs of continuing the war exceed the potential gains. In line with the analysis above, a number of reasons present themselves:

1. Cognitive biases. Leaders on both sides may genuinely believe their situation to be better than it is due to optimism bias. They may also be stuck in a sunk cost fallacy, believing that after having invested so much in the war, they must invest more in order to recoup their losses. In Russia’s case, optimism may be due to a belief that sooner or later the West will tire of the war, and abandon Ukraine. In Ukraine’s case, optimism may be due to endless assurances from Western politicians that they will support Ukraine for “as long as it takes.” Ukrainian leaders may also believe that they will be able to gradually obtain more and more powerful weapons from their Western allies, in the end tipping the war in their favor. The West’s incremental escalation during the war, gradually handing over different types of weapons that were once ruled out of bounds, has arguably encouraged this attitude. In addition, the fact that Ukraine’s military position has declined quite gradually may have made the decline more difficult to acknowledge than if it had resulted from a sudden defeat. A decisive shock may be required to jolt perceptions.

2. Internal political and bureaucratic dynamics. Both Putin and Zelensky may fear for their political future if they compromise. Of the two, Zelensky’s position looks the weaker, and so this factor may be a particular problem for him. Zelensky may face intense pressure from powerful forces within Ukraine who are resistant to any compromise. This could include elements of the military, including those associated in one way or another with the nationalist right.

3. Imperfect information. It would not be surprising if both President Putin and President Zelensky were being fed unduly positive reports by their subordinates. Information about the state of their opponents, including their losses, their morale, and their productive capabilities, is uncertain. So too are factors such as the likely future behavior of other countries, in particular of Ukraine’s Western backers. All this may feed into the cognitive biases mentioned above.

4. Distrust/Commitment credibility. It could be that Putin and Zelensky are in reality fully aware of the reality of their situation. However, to make peace they must not only perceive that they cannot achieve absolute victory but must also perceive a way out. They may not do so, because they so distrust one another that they consider it probable that the other will break any agreement, leaving them even worse off than before. The level of mutual distrust between Ukrainian and Russian political leaders is indeed enormous, due to perceptions of past behaviors. The Ukrainians see the Russians as having broken promises to guarantee Ukrainian security made by Russia in the Budapest Memorandum of 1994. They argue that Russia will use any ceasefire to strengthen itself prior to relaunching its war of conquest against Ukraine. As Zelensky said in January 2024, “A pause on the Ukrainian battlefield will not mean a pause in the war. A pause would play into [Russia’s] hands. It might crush us afterward.¹⁷” Russians, meanwhile, use exactly the same argument, but in reverse – Ukraine will use any ceasefire to rearm, and then restart the war on terms that are more favorable to itself. The experience of Ukraine’s failure to enact key clauses of the 2015 Minsk II agreement that was designed to end the war in eastern Ukraine, above all the failure to grant some degree of autonomy to Donbass, is often cited in this regard. So too are statements by Western leaders, such as former German Chancellor Angela Merkel, that the Minsk agreement was never meant to be fulfilled but was designed simply to give Ukraine time to recover its strength¹⁸. This has a powerful effect on Russian attitudes towards a potential ceasefire in the current war. Thus, Russian foreign minister Sergei Lavrov commented in December 2024 that “the West is starting to talk about a ceasefire as a means to give Ukraine a respite, and give themselves the opportunity to once again pump Ukraine up with modern long-range weapons. This, of course, is not a path to peace.¹⁹”

5. Spoilers. There is a common assumption that America’s allies will inevitably fall in line with whatever policy the United States pursues. Thus, if the United States pushes for peace in Ukraine, European states will accept whatever deal is being proposed. This is not necessarily true. Some European countries, most notably Poland and the Baltic States, but to a lesser degree also France and the United Kingdom, consider preventing a Russian victory to be a vital national interest and have committed themselves so fully to the Ukrainian cause that it is quite possible that they will act as spoilers of any US-led peace effort, urging Ukraine to stand firm, and offering to make up for any decreases in American assistance.

Policy Conclusions

To date, the United States and its allies have conducted a two-pronged policy based on a) military and economic support to Ukraine, and b) economic pressure on the Russian Federation. One can identify three stages to this policy. At first, immediately following the 2022 Russian invasion of Ukraine, the aim was simply to prevent Ukraine being defeated. Later, following Ukrainian successes in late 2022, it would appear that Western states believed that Ukraine could actually emerge militarily victorious, and military aid to Ukraine was premised on that possibility. Third, following the failure of the 2023 Ukrainian offensive, policy shifted away from achieving victory towards trying to prevent a further deterioration of the Ukrainian position so that when negotiations eventually begin, Ukraine can participate in a position if not of strength then at least not of enormous weakness.

Despite the shifting aims, however, the basic policy has remained the same: strengthen Ukraine and weaken Russia. This has not been successful. The longer the war has continued, the more the balance of power has shifted in Russia’s favor. This trend seems likely to continue, and it is probable that the longer Ukraine waits to make peace with Russia, the worse its position will be. In the meantime, it will suffer continued losses of people and physical infrastructure. It is clear, therefore, that the time has come for a shift in policy away from helping Ukraine fight its war and towards peacemaking.

The analysis above suggests certain conclusions as to what would best serve the interests of peace:

1. Increased pressure on Russia is unlikely to bring the war to an end in the short to medium term. Abandoning all military, political, and diplomatic pressure on Russia will increase its optimistic understanding of its relative strength, and thus encourage further its pursuit of absolute victory. For this reason, such an abrupt change in policy is not advisable. That said, increasing the pressure is unlikely to be any more productive than eliminating it. It is improbable, for instance, that the volume of military supplies to Ukraine will ever reach that provided in the winter of 2022-23, a volume that was insufficient to enable the Ukrainian 2023 offensive to succeed. However much aid Western states provide to Ukraine henceforth, the Russian military will almost certainly continue to enjoy an advantage over Ukraine, and the pressure on the Russian government to end the war on disadvantageous terms will therefore necessarily be weak, at least in the short to medium term. It is possible that continued pressure will eventually convince the Russian leadership that it cannot achieve its most important objectives by military means and also convince it that a continuation of the current situation is harmful to its interests. This, though, is likely to take a very long time, during which Ukraine will continue to suffer. Moreover, even if the Russian leadership is convinced in this way, the commitment credibility problem may mean that it might remain unwilling to abandon its objectives and might prefer to continue the war rather than accept a peace that it believes will prove short-lived. We can conclude, therefore, that while it would be unwise to significantly decrease pressure on Russia, the path to peace probably does not lie through doing the opposite.

2. Negative and positive inducements to Ukraine are more likely to bring the war to a quick conclusion. As a general rule, it is the weaker party that brings the war to an end, by finally recognizing its position and either unilaterally ceasing the struggle or signaling its willingness to make concessions. Given that Ukraine is the weaker party, the surest and fastest way to peace therefore probably lies in negatively altering its perceptions of its ability to achieve key objectives by means of negative inducements (diplomatic pressure, withdrawal of aid, etc.), while also providing it some positive inducements, such as promises of economic assistance following the end of the war.

   One of the problems of Western policy over the past decade, from the Maidan revolution of 2014 onwards, has been that Western states have been unwilling to pressure Ukraine to make the concessions required for a peaceful settlement of its political conflict with Russia. This has had fatal consequences. For instance, the failure to induce Ukraine to fulfil the promises made in the Minsk II agreement to grant autonomy to Donbass led to the collapse of the agreement, and arguably therefore contributed to the outbreak of full-scale war in 2022. Meanwhile, the policy of incremental escalation pursued by the USA and its allies has possibly convinced Ukrainian leaders that they will always eventually be able to push their Western allies to go one step further. Dangling false hopes in front of Ukraine – for instance, promises of eventual NATO membership or hints of some form of direct Western involvement in the war – encourages optimism bias and prevents Ukraine from correctly perceiving the weakness of its position. The time has come for firm diplomacy that aligns perceptions with reality.

   A careful balance will be required between pressuring Kyiv enough to induce a change in its perceptions that encourages it to seek peace, and pressuring it so much that it changes Moscow’s perceptions in a way that encourages it to further pursue war. The correct balance will be difficult to find. But it is clear that to date the balance has been skewed in the wrong direction, and that a move in the direction of more pressure on Kyiv is required.

3. Such firmness should assist with the problem of internal opposition to peace within Ukraine. Overcoming that opposition will be difficult, but if President Zelensky can tell both the Ukrainian people and key players within the political elite and the military that future Western support is dependent on making peace, then his hand will be considerably strengthened.

4. A formal peace treaty is much preferable to a Korean-style ceasefire. Negative and positive inducements will be unlikely to succeed as long as both parties remain suspicious that the other side will use a ceasefire as a breathing space to rearm prior to restarting hostilities. A Korean-style ceasefire is therefore best avoided. A formal treaty, by contrast, commits both parties not merely not to resume fighting but also to a recognition of the resolution of their differences. Formal treaties can, of course, be broken, but doing so is a much more significant breach of promise than ending a ceasefire. Treaties thus provide a degree of reassurance that ceasefires do not.

5. Issues such as territorial boundaries should be formally resolved in any treaty. By the same logic as above, it is best that any treaty be as comprehensive as possible and not leave issues hanging that might be the basis for future disputes and serve as an excuse for recommencing the war. For this reason, it would be better if any treaty ending the Russo-Ukrainian war formally recognized the new border between the two countries. Most proposals to end the war suggest that Ukraine should de facto recognize the loss of territory but not de jure, because this would be politically easier to accept. However, in the absence of de jure recognition, Russia and Ukraine will be locked into a permanent territorial dispute that will perpetually endanger the peace. Knowledge that this will be the case accentuates the credible commitment problem.

6. Both Ukraine and Russia need reassurance that the end of the war will truly be the end, not merely a respite used by the other side to recover prior to a restart. This is perhaps the key to a successful peace process, as it is clear that at present neither side believes this to be the case. The importance both Ukraine and Russia attach to the issue of Ukraine’s potential NATO membership reflects this. To Ukraine, NATO membership is the guarantee par excellence that Russia will be unable to attack it again. This is why Zelensky has recently expressed a willingness to forego other benefits in order to achieve this single objective. For Russia, however, a Ukraine in NATO is one that could potentially restart the war but this time with the backing of the whole of the Western alliance. From a Russian point of view, the only way of guaranteeing that Ukraine will not restart the war is rendering it incapable of doing so, which means its neutrality and de-militarization.

   This creates a serious dilemma for any peacemaker: security guarantees for Ukraine are essential for overcoming the credible commitment problem. Without them, Ukraine may continue to fight even if its leaders recognize that its position is hopeless. But what are security guarantees for Ukraine are perceived as security threats by Russia. And likewise, what Russia sees as security guarantees are perceived as security threats by Ukraine. Squaring this particular circle will be extremely difficult, but arguably it is the most important task of any mediator, as unless it is circled the war cannot end.

   Examples of how perhaps this could be done include leaving the issue of NATO membership open, but with guarantees that NATO troops and long-range weaponry will not be permitted in Ukraine; accepting NATO membership for Ukraine but reconfiguring the entire European security structure in such a way that Russia no longer views NATO as threatening; the provision of some sort of peacekeeping force that neither side considers hostile; making Ukraine neutral but providing security guarantees in some manner that does not include NATO; or something else entirely. Some of these potential solutions are rather more implausible than others. Some may also require considerable arm twisting of the Ukrainian leadership by American diplomats. But what is clear is that providing the necessary reassurances to both sides will require very original thinking.

7. Efforts will be required to neutralize spoilers. States such as Poland, Latvia, Lithuania, and Estonia fear that anything short of a decisive Russian defeat will embolden Russia in a way that could eventually threaten them. They will therefore be inclined to encourage Ukraine to resist any peace efforts. To prevent this, they too will require reassurance. This will probably require some sort of commitment by the United States to the continued defense of Europe.

Final Conclusions

Of all the issues mentioned above, the credible commitment problem is possibly the most important. A combination of positive and negative inducements may alter the perceptions of one or both sides in such a way as to make them more amenable to peace, but this cannot be guaranteed. Furthermore, any step that makes one party’s perceptions more pessimistic, and so renders it more willing to negotiate, is likely simultaneously to make the other party’s perceptions more optimistic, and so render it less willing to do so. Moreover, even if the parties’ perceptions are altered in the desired manner, they will not act in the desired manner if they remain convinced that any ceasefire will only be a temporary pause used by their opponents to strengthen their position prior to recommencing hostilities.

Studies of war termination suggest that warring states may forego secondary objectives if they are able to achieve another objective of very considerable value. At that point, as one study notes, the side that has achieved a super-valuable objective could continue fighting but “does not because the costs of going further threaten to escalate the conflict, and it is less motivated to keep going because additional increments of the good are not as valuable.²⁰” It is important, therefore, to identify what those at war consider “super-valuable” and seek to guarantee that. In the case of Russia and Ukraine, it would appear that the most valuable thing sought by both sides is security, defined as freedom from fear of a future conflict. Arguably, it was Russian fears of the movement of Ukraine into the NATO camp, of apparent Ukrainian hostility, and of an escalation of the war in eastern Ukraine into a wider conflict involving Western powers, that motivated Russia’s leaders into launching a preventive war against Ukraine. Likewise, fears that anything less than victory may produce such a result further down the road persuades Russian leaders to keep on going. At the same time, having been invaded by Russia, Ukraine has well-founded fears of future Russian aggression and seeks a settlement that protects it against further such aggression hereafter.

Any settlement of the war must therefore address the issue of the future security of both parties. That means that any third party attempting to mediate between the two must take seriously the security concerns of both belligerents. In particular, ignoring the concerns of the stronger party is very unlikely to result in successful war termination. Accepting this will require a considerable change in attitude from Western leaders. It is also a precept that many in the West will doubtless strongly resist. Overcoming this resistance may require some strong diplomacy and will involve taking steps that incite sharp criticism from some quarters. The potential benefits, however, far outweigh the risks.

Paul Robinson (DPhil, Oxford University) is professor of public and international affairs at the University of Ottawa. His research and teaching embraces military ethics, Russian history, security and defence policy. He is the author or editor of 14 books. Prior to his graduate studies, he served as a regular officer in the British Army Intelligence Corps from 1989 to 1994, and as a reserve officer in the Canadian Forces from 1994 to 1996.

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2. William Zartman, International Conflict Resolution After the Cold War (Washington, DC: The National Academy Press, 2000), 228.

3. Chione Robinson, “A Theory of War Termination for Peacemakers,” Canadian Forces College Review, 2020: 88.

4. Robinson, “A Theory of War Termination,” 83.

5. Shawn T. Cochran, War Termination as a Civil-Military Bargain: Soldiers, Statesmen, and the Politics of Protracted Armed Conflict (Houndmills, Palgrave Macmillan, 2016), 2.

6. Dan Reiter, How Wars End (Princeton: Princeton University Press, 2009), 220.

7. Reiter, How Wars End, 222. Carmela Lutmar, “War Termination,” Oxford Research Encyclopedia of Politics (Oxford: Oxford University Press, 2017); Feargal Cochrane, Ending Wars (Cambridge: Polity, 2008), 75.

8. Reiter, How Wars End, 4

9. Lutmar, “War Termination.”

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13. “Putin Says Almost 700,000k Russian Troops Fighting in Ukraine,” The Moscow Times, 16 June 2024, https://www.themoscowtimes.com/2024/06/15/putin-says-almost-700k-russian-troops-fighting-in-ukraine-a85419.

14. Samya Kullab and Voldymyr Yurchuk, “Desertion Threatens to Starve Ukraine’s Forces at a Crucial Time in its War with Russia,” AP, 29 November 2024, https://apnews.com/article/deserters-awol-ukraine-russia-war-def676562552d42bc5d593363c9e5ea0.

15. David Brennan, “Russia Sees ‘No Grounds for Negotiations’ with Ukraine, Putin Spokesman Says,” ABC News, 4 December 2024,https://abcnews.go.com/International/russia-sees-grounds-negotiations-ukraine-putin-spokesperson/story?id=116441134.

16. Alexander Butler, “Zelensky says Ukraine could temporarily cede territory to Russia in exchange for Nato membership,” The Independent, 30 November 2024, https://www.independent.co.uk/news/world/europe/zelensky-putin-russia-ukraine-war-ceasefire-trump-b2656221.html.

17. Jim Heintz and Illia Novikov, “Ukraine’s Zelenskyy rules out a ceasefire with Russia, saying Moscow would use it to rearm,” CTV News, 11 January 2024, https://www.ctvnews.ca/world/ukraine-s-zelenskyy-rules-out-a-ceasefire-with-russia-saying-moscow-would-use-it-to-rearm-1.6721024.

18. “Attempt to ‘Give Ukraine Time:’ Merkel on Minsk Agreement,” TASS, 7 December 2022, https://tass.com/world/1547141.

19. “Russia Says West Seeking Ukraine Ceasefire to Rearm Kyiv amid Scholz’s Visit,” First Post, 2 December 2024, https://www.firstpost.com/world/russia-says-west-seeking-ukraine-ceasefire-to-rearm-kyiv-amid-scholzs-visit-13840919.html.

20. Reiter, How Wars End, 45.