Wars can end with a peace treaty or ceasefire agreement; they can end with the victory of one side; or they can subside over time. The latter two scenarios reflect the so-called “might makes right” principle and are associated with problems for the weaker parties. Peace treaties and ceasefire agreements, on the other hand, are based on the rule of law principle, which, as a pillar of the liberal world order, encompasses norms of freedom and equality.

The following pattern has emerged over the past eighty years: From 1945 until the end of the 1970s, victory by one party to the conflict was the most common way to end a war. Since then, most wars have subsided without an explicit peace treaty or ceasefire agreement or even the victory of one side. Initially, peace treaties and ceasefire agreements played a secondary role and only after the end of the Cold War, did the number of wars that ended with peace treaties and agreements surpass the number of unilateral victories.

How did this come about? Peace treaties and ceasefire agreements are more commonly used to end interstate wars than intrastate wars. Between 1945 and 2025 there have been more intrastate wars than interstate wars; however, the role of international actors in pacifying intrastate conflicts has increased considerably since the 2000s. This particularly includes the United Nations, but also regional organizations and third-party countries. These factors have contributed to a significant increase in resolving conflicts through peace treaties or agreements.

Looking ahead, this trend can be expected to continue as the number of global and regional organizations with explicit security mandates has increased considerably over the past eighty years. Yet, organizations such as the United Nations or the African Union require the consent of their members to act in this capacity, which cannot be taken for granted in times of increasing populism and nationalism. This, in turn, would lead to a decrease in peace treaties and ceasefire agreements and a resurgence of “might makes right” in conflict resolution.

Diana Panke is professor of international relations at the Otto Suhr Institute of Political Science, Freie Universität Berlin.