The weight of an 896-page biography alone serves as an interrogation: Why should I commit myself to undertake such a huge reading project? In the case of H. W. Brands's magisterial life of Franklin Delano Roosevelt, there is no paucity of worthy responses. "Traitor to His Class," writes Pulitzer Prize–winning historian David Oshinsky, "will quickly emerge as the finest one-volume biography of F.D.R." Presidential historian Michael Beschloss agrees, enthusing that the book "deserves a wide audience, especially among those younger Americans who need to be told why we all owe so much to F.D.R." In this time of economic and international turmoil, the president who guided the country through the Depression and World War II has reemerged as a man who is important to the current generation.