Of the dozens of men who have served as US president, Franklin Delano Roosevelt had a particularly close connection with the citizens he served. The only president elected to four terms, Americans hung FDR's picture up in their homes, wrote him thousands of letters, and regularly tuned in to listen to his fireside chats.

My guest would say that much of the depth, gravitas, and empathy Roosevelt was able to convey to the country was not something inborn, but in fact grew out of a tragedy which befell him at the age of 39: the contraction of polio. Jonathan Darman is the author of Becoming FDR: The Personal Crisis That Made a President, and today on the show, he paints a portrait of what Roosevelt was like before he got polio, and how, despite charm and ambition, he was considered shallow and a political lightweight. We then discuss what it was like for FDR to get polio, what he did during years of bedridden convalescence, and how the disease and his rehabilitation changed him. We talk about how the influence of FDR's polio experience can be seen in the way he guided the country through the Depression and WWII, and the lesson in realistic optimism he offers us today.

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