Nancy Koehn | Charlie Rose
Nancy Koehn, historian and Harvard Business School professor, talks about courage and leadership.
In her new book "Forged in Crisis: The Power of Courageous Leadership," Professor Koehn explores the lives of polar explorer Ernest Shackleton, President Abraham Lincoln, abolitionist Frederick Douglass, Nazi-resisting clergyman Dietrich Bonhoeffer, and environmental crusader Rachel Carson.