The first face-to-face peace talks between Ukraine and Russia since March 2022 took place in mid-May 2025 in Turkey. Russian President declined to attend, sending a mid-level delegation. The sides agreed to prisoner swap but failed to reach an agreement on ceasefire. A day after the meeting, Russia unleashed the largest drone attack on Ukraine since the start of the war. President Zelensky concluded that “Russia does not want to end this war.” Most observers would agree. How can world leaders bring an end to this war? As former US Ambassador to Ukraine Bridget Brink says, history has some useful lessons.
There is a historical pattern with many wars whereby, after an initial period of rapid advances and retreats, they settle into a prolonged stalemate. The war continues for years before coming to a semi-conclusion where the fighting stops based on where the frontlines were when the stalemate set in. An outside observer would be struck by the waste – why does the war continue for years with more young lives lost when the two sides just end up exactly where they were at the start? Would it not be rational for both sides to come to an agreement to settle the war much earlier? This appears to be the case now in Ukraine, and many outside observers are asking precisely this question. The answer which many reach is that it is Ukraine’s futile insistence on regaining its lost territory which is prolonging the war. Elon Musk, for instance, tweeted that President Volodymyr Zelensky wants a ‘forever war, a never ending draft meat grinder’ and has slammed US military aid to Ukraine. The facts of the case and the political science and history of war termination, however, show that Musk is wrong – support for Ukraine does not prolong the war, but rather is the best way to bring it to an end.
The literature on war termination identifies three key reasons why wars ‘drag on’ – incomplete information, commitment problems, and the shadow of future interactions. The incomplete information theory of war termination builds on an influential theory of why wars begin. According to this view, if all the protagonists to a war knew – with certainty – how the war would end, they would be able to come to an agreement in which each party would get what they would have gotten in the war, minus the costs of fighting. The reasons why wars occur, in this view, is that neither side can know what the outcome will be for sure and so can imagine that they will gain more from fighting than settling. Wars come to an end, by the same token, when it becomes clear how strong (in the broad sense) each side is relative to the other and a deal can be made reflecting these strengths. According to this view, the problem with the Ukraine War today is that this clarity is lacking. Both sides can therefore imagine scenarios in which they gain more from continuing to fight than from conceding – Russia might imagine that they can grind Ukraine down; Ukraine, that mounting losses might convince Putin to stop, or that they might even lead to his overthrow. There are many variables which go into this calculation such that each side believes they have a plausible route to victory and hence no need to make peace.
As an answer to the question – “why won’t Russia make peace” – the incomplete information perspective provides a compelling answer. The more doubt there is that the US will continue to support Ukraine, the better the future trajectory of the war is from the Russian perspective and hence the less likely Russia is to make peace. One might imagine that a prospective cut off of external support to Ukraine would at least make Kyiv more likely to negotiate, but there is a hard limit to how bad a deal Ukraine would accept, and this brings us to credible commitment and the shadow of the future.
The credible commitment perspective notes that a key obstacle to peace is the danger that a combatant nation perceives its opponent exploiting a peace deal to their advantage in a future war. This literature suggests several mechanisms whereby belligerent states might be able to credibly reassure their opponents of their intentions – for instance, through disarmament or by allowing peacekeepers to be placed on the frontlines. The problem with this perspective here is simple – Russia’s intentions are not benign. And at least so far, all the evidence points to this conclusion: Russia’s strong opposition to Ukraine joining NATO leaves Ukraine without an established military alliance to defend it should Russia attack again; the infamous Istanbul memorandum, which outlined Russia’s proposals for Ukraine, took this even further by asking Ukraine to limit the size (100,000 personnel max) and equipment (no foreign weaponry) of the Ukrainian Army. Shouldn’t it be the aggressor who reduces its military after the conflict to re-assure Ukraine of its benign intentions?
It is this ‘shadow of the future’ – the prospect that a peace deal on Russian terms leaves Ukraine defenseless in future – which further puts a hard floor on what Ukraine can accept, regardless of US pressure. The question for the international community, therefore, is to resolve the uncertainty which allows Russia to continue to believe it can win the war (and maybe help it solve its domestic problem) by stepping up aid to Ukraine and sanctions on Russia. The aim should be to break Russia’s theory of victory by making it less plausible that it can obtain its maximalist aims on the battlefield. Europe has an obvious incentive here – Putin might stop at Ukraine, but many observers and countries believe he will not.
Decades of over-reliance on the United States have left Europe vulnerable to an attack from the East, and this cannot be reversed overnight. Other developed democracies also have an incentive to prevent a Russian victory. International relations research has shown that the post 1945 norm against territorial conquest has had a significant effect in reducing the risk of war worldwide – but this norm needs to be enforced or it will break down. The most recent findings from the Institute for Economics and Peace (IEP) suggest that this norm has started to break down. IEP finds that as of 2024, the world had the highest number of countries engaged in conflict since World War II. It is not a surprise that they name the war in Ukraine as one of the primary drivers of the global fall in peacefulness. Another problem is the fact that people who fought in WWII and therefore can remind us how important this norm is are almost gone.
Other second order consequences of Russia’s aggression need to be remembered – if the lesson of the Ukraine War is that you can invade your neighbors and get away with it as long as you have nuclear weapons, what is this likely to do for nuclear proliferation? Whether you intend to invade your neighbors or to deter an invasion, acquiring your own nuclear arsenal is the obvious answer. And just a reminder that in early 1990s Ukraine was the third largest nuclear power in the world. It did agree to get rid of its nuclear arsenal as a result of the 1994 Budapest Memorandum on Security and Assurance. In return, the US, UK, and Russia agreed to guarantee its security and territorial integrity. Given the events of the last three years, few countries would agree to get rid of their nuclear weapons.
Therefore, as the discussion of peace is on-going, we suggest that the world leaders mine history and international relations theory for lessons. In particular, it should include two things. First, reduce uncertainty around who can win this war by stepping up aid to Ukraine, sanctions on Russia and showing unity in their commitments. Second, ensure that real security guarantees are on the table. EU President Ursula von der Leyen has spoken of turning Ukraine into a ‘steel porcupine’, while individual leaders such as Emmanuel Macron and Keir Starmer have spoken of deploying European forces directly to Ukraine. Both solutions, however, require radical changes in European foreign and defense policies.
Steep increases in military spending will be required, which will mean less left over for domestic priorities. The populist right, no doubt encouraged by Moscow, will raise merry hell about this. European leaders will therefore have to be clever – ideally military efficiency should guide procurement policies, but public support is a key element of national power. Rearmament should therefore be aimed in part to re-industrialize precisely those ‘left behind’ areas of Europe most vulnerable to the populist threat, such as the North of England or Eastern Germany. At the same time, European states should seek greater efficiencies by promoting the standardization of military equipment across the continent with a focus on reducing dependence on the United States. All of these policies will involve significant costs and the rupture of old relationships. But these costs are essential for peace in Europe.
Further Reading on E-International Relations
- Why Both Ukraine and Russia Need Peace after a Third Summer of War
- Opinion – Examining the Conditions for Durable Peace in Ukraine
- Opinion – Reinhold Niebuhr and the Future of US Support for Ukraine
- How the War in Ukraine Strengthened Latvia’s European Credentials and International Standing
- Opinion – Five Scenarios for the War in Ukraine Under a Trump Presidency
- Ukraine and the Geopolitics of Legitimacy
