What is true leadership? Can it be taught?

During TEDxESCP, Bob Davids – entrepreneur and visionary – explains the difference between leadership and management and stresses the importance of leadership without ego.
According to Mr. Davids, management implies control and if you push people you cannot predict what they will do.
Analyzing examples of famous leaders like Gandhi, he affirms that if you can lead people and get them to follow you, then you have the skills to be a leader.
But leadership is a gift and cannot be bought.
Leadership without ego is thus the most valuable commodity and the rarest in the planet.