Nine experts on Cold War history offer commentaries about John Lewis Gaddis's Pulitzer Prize-winning biography of George F. Kennan, the first head of the U.S. State Department's Policy Planning Staff. The commentators come from several countries and offer a wide range of perspectives about Gaddis's George F. Kennan: An American Life , published by Penguin Books in 2011. Although most of the commentators express highly favorable assessments of the book, they also raise numerous points of criticism. Two of the commentators, Barton J. Bernstein and Anders Stephanson, present extended critiques of Gaddis's biography. The forum concludes with a reply by Gaddis to all the commentaries, especially those by Bernstein and Stephanson.