The Russo-Ukrainian War: 2014–???? Why did it start? Why does it continue? How may it end?

Abstract

The Russo-Ukrainian War began in 2014 and expanded into a full-scale invasion in February 2022. This review explains its causes, persistence, and most likely outcome, giving greater weight to causation theories that generated specific prior warnings. The principal cause is the collision among NATO enlargement, Russia’s exclusion from decision-making authority in the Euro-Atlantic security order, and Ukraine’s growing de facto military integration with Western states—a danger foreseen by Kennan, Burns, Mearsheimer and others. The ‘Cuban Missile Crisis in reverse’ identifies another concern: potential nuclear strike systems in Ukraine could sharply reduce warning time as arms-control regimes eroded. NATO had not deployed nuclear missiles in Ukraine, and Russia had nonviolent alternatives. A preventive-war calculation—attacking before an adverse military balance hardened further—best explains why Russian leaders accepted the costs of aggression. The third reason is Russian fears of NATO preference for “dismantling Russia” into several smaller countries, which are well-documented in accounts by politicians from NATO countries. Evidence that Minsk Agreements bought time to strengthen Ukraine, reports of Western resistance to an early 2022 compromise, and continued de facto Ukraine’s integration into NATO gave Russia rational grounds to distrust Western promises. Russia’s treaty violations gave Ukraine equally strong grounds for mistrust; a settlement must therefore rely on verification. Russia’s failed rapid campaign to capture Kiev turned into an attritional war. Foreign support prevented Ukraine’s defeat, while Russia’s mobilization base and partners enabled continued fighting. Because U.S. officials identified weakening Russia as an objective, ‘punishing Russia regardless of the cost to Ukraine’ merits consideration as a partial, not exclusive, explanation of war duration. Neither decisive victory nor comprehensive peace is likely. The most probable outcome is a Korea-type armistice: large-scale combat stops along a fortified line, claims remain unresolved, forces remain deployed, and outside support continues. This is a conditional forecast, not a policy preference.