As I set out five years ago to write a biography of one of the most recognizable women on the planet, the first question was why do it. The second was how. Neither answer came easily. I had written often about Michelle Obama as the Chicago correspondent for The Washington Post. During the 2008 campaign, I trailed her to Iowa, New York, Texas and a handful of other states. I interviewed her friends on the South Side and tracked her path through Princeton and Harvard and back to the neighborhoods of her youth, where she worked to unstack the deck for working class African Americans.