This week on Facing the Future, we hear from Harvard Kennedy School of Government professor of public service David Gergen, who served as a White House Advisor to four US presidents (Nixon, Ford, Reagan, and Clinton). Gergen has written a new book called "Hearts Touched with Fire: How Great Leaders are made." His main conclusion: It's time for the Baby Boomer generation to exit stage left and pass the baton of leadership onto Generation X, Millenials, and Gen-Z.