The tall man=power equation may simply be part of the male-female power differential.
Men are taller because of hormonal influences, to be sure.
Napoleon aside, tall men are more likely to win the popular contest in presidential votes and to be re-elected once in office (Stulp, 2013).
Their greater leadership potential may have something to do with the fact that tall men have higher self-esteem (whether or not deserved), are happier, and less likely to feel jealous toward other men.
Second, being “looked up to,” quite literally, may at some subconscious level lead taller men to feel that they have superior qualities.