Leadership theory and the value of this progression for today’s organizational leader

Leadership theory has developed over the years.  Consider the progression from power control in the early 20th century through trait theory, group, behavior, transformation to authentic, spiritual, servant, and adaptive theories of the 21st century.

Discuss the value of this progression for today’s organizational leader.  Has this progression benefited the practice of leadership?  Is the Christian leader advantaged over the non-Christian leader, given both practice the underlying principles of these theories?