Emotional Intelligence - Is It the Foundation of Great Leadership?

Decades ago, this concept of Emotional Intelligence in leadership would not have appeared in many writings about what makes great leadership. There are plenty critics of the concept and its relationship to successful leaders. My intent is not to defend nor prove any research that has been done. Rather, I want to share my years of observation and study of leaders and the impact of EQ.  Let's start with the definition of Emotional Intelligence - skill in perceiving, understanding, and managing emotions and feelings.  There are more expanded and varying versions but this one captures the essence of the definition.