24 February 2022 was not the beginning of Russia's war on Ukraine. Back in 2014, Russia illegally annexed Crimea from Ukraine, bolstered a separatist conflict in the Donbas region, and attacked Ukraine with units of its regular army and special forces. In each instance of Russian aggression, the U.S. response has often been criticized as inadequate, insufficient, or hesitant. The Moscow Factor: U.S. Policy toward Sovereign Ukraine and the Kremlin is a unique study that examines four key Ukraine-related policy decisions across two Republican and two Democratic U.S. administrations. Author Eugene M. Fishel asks whether, how, and under what circumstances Washington has considered Ukraine’s status as a sovereign nation in its decision-making regarding relations with Moscow. This study situates the stance of the United States toward Ukraine in the broader context of international relations. It fills an important lacuna in existing scholarship and policy discourse by focusing on the complex trilateral—rather than simply bilateral—dynamics among the U.S., Ukraine, and Russia, in 1991–2016. This book brings together for the first time documentary evidence and declassified materials dealing with policy deliberation, retrospective articles authored by former policymakers, and formal memoirs by erstwhile senior officials. The study is also supplemented by open-ended interviews with former and returning officials.