I recently read an interesting report about research on the intersection between power and leadership in the April, 2017 issue of the Monitor on Psychology by K. Weir. She called it "Powerplay." The major finding was that people who experience themselves as powerful and those who see themselves as powerless have different perspectives on the world.
The powerless attend to the challenges in striving toward a goal and proceed carefully, while the powerful see an unimpeded path to success and take risks. The powerful are prone to creating problems for others because they focus on what they want and are less aware of the needs and agendas of others. Their lack of empathy, failure to see the magnitude of upcoming complications, and their tendency to quick, impulsive decrees can be destructive to their social group and to the very problems that they are trying to tackle.
Yes, the powerful may be more egocentric; the powerless, more prosocial. However, there are moral and ethical powerhouses. It is important that powerful leaders be held accountable.
I agree with her conclusion. It seems to me that we humans want leaders who see themselves as powerful, but it is up to us to select those powerful leaders who have integrity. It would be unfortunate indeed not to be aware of a leader's having destructive power over any group to which we belong.