Roosevelt emerges from the pages of the documents pertaining to the history of the Yalta Conference as a true founder of the imperial presidency, running his own foreign policy by reducing the State Department to little more than an instrument for the implementation of policy devised in the White House. The result was not only the close association of U.S. foreign policy with FDR and his vision of the world but also the inability of anyone but the president himself to conduct the three-sided diplomatic exercise that inevitably came to an end after his sudden death. Roosevelt created a system in which the United States assumed the role of mediator and exercised a kind of influence on world affairs that it had not had before. With Roosevelt gone, the tripartite contest turned into a bipolar confrontation exacerbated by the implosion of the British Empire in the decade following the end of the war.

—Serhii Plokhy, Yalta, (London: Penguin, 2010), Epilogue.