"I am Spartacus!" The difference between Power and Leadership

I love this scene from the movie Spartacus. Lawrence Olivier's Crassus has the power over life and death. But, who's the real leader here? You can tell from the look on Olivier's face that he knows it isn't and never will be him. I guess he should have thought laterally: Kirk Douglas is the only one NOT shouting 'I am Spartacus'. Learning point? There are people with power in your organization. That's often confused with leadership. The two are very different.