Eurasian Disunion: Russia's Vulnerable Flanks examines the impact of Moscow's neo-imperial project on the security of several regions bordering the Russian Federation, analyses the geopolitical aspects of Kremlin ambitions, and makes recommendations for the future role of NATO, the EU, and the United States in the Wider Europe. Russia's attack on Ukraine and the dismemberment of its territory is not an isolated operation. It constitutes one component of a broader strategic agenda to rebuild a Moscow-centered bloc designed to compete with the West. The acceleration of President Vladimir Putin's neo-imperial project has challenged the security of several regions that border the Russian Federation and focused attention on the geopolitical aspects of Kremlin ambitions. This book is intended to generate a more informed policy debate on the dangers stemming from the restoration of a Russian-centered "pole of power" or "sphere of influence" in Eurasia. It focuses on five vulnerable flanks bordering the Russian Federation--the Baltic and Nordic zones, East Central Europe, Southeast Europe, South Caucasus, and Central Asia. It examines several pivotal questions, including the strategic objectives of Moscow's expansionist ambitions; Kremlin tactics and capabilities; the impact of Russia's assertiveness on the national security of neighbors; the responses of vulnerable states to Russia's geopolitical ambitions; the impact of prolonged regional turmoil on the stability of the Russian Federation and the survival of the Putinist regime; and the repercussions of heightened regional tensions for U.S., NATO, and EU policy toward Russia and toward unstable regions bordering the Russian Federation.