Daniel Day-Lewis' portrayal of the 16th President in Steven Spielberg's new movie "Lincoln" is very different from the one we've come to know from previous movies, history books, or the animatronic Abe at Disneyland. Other presidents have led us in crises, steered us through wars, been cut down by assassins. But Abraham Lincoln fascinates us like no other. In fact, there have been over 15,000 books written on Lincoln. Madeleine Brand talks to Dr. Ronald White, one of the country's foremost experts on The Great Emancipator, to find out why he is still such an important historical and cultural figure.