"Forged in Crisis" author on the makings of a great leader
History offers many definitions of what it takes to be a great leader. A new book from Harvard Business School historian Nancy Koehn called "Forged in Crisis: The Power of Courageous Leadership in Turbulent Times" examines the lives, successes and failures of five historical leaders including explorer Ernest Shackleton, Abraham Lincoln and Frederick Douglass. Koehn joins "CBS This Morning" to discuss the hallmarks of a great leader and the importance of the adversity they experienced along the way.