Working Under Phi News Today

Challenge. with us tonight is ambassador william burns, former u.s. ambassador to russia from 05 to 08. he served as a diplomat for over three decades, working under phi presidents. holds the highest rank as a career ambassador. he is currently president of the carnegie endowment for international peace. he also happens to be the author of a new book, "the back channel: a memoir of american diplomacy and a case for its renewal." thanks for being was. >> thanks so much. its great to be with you. ...