Four eminent historians talk about how history has shifted with Barack Obama's election.
Bernice Johnson-Reagon, cultural historian and civil rights activist, who founded the African-American women's a cappella ensemble, Sweet Honey In The Rock
Robert Kagan, senior associate at the Carnegie Endowment for International Peace and author of The Return of History and the End of Dreams
Victor Davis Hanson, senior fellow in classics/military history at the Hoover Institution, Stanford University
Annette Gordon-Reed, professor of law at New York Law School and author of The Hemingses of Monticello: An American Family