Kal-El (Earth-5029)

"We are the Justice League, and our sole purpose is to defend the people of Eart at all costs. That's what you don't understand. And I don't think you ever will. You're blinded by ego and vengeance, and one of these days it will be your downfall."

- Superman

Superman is the leader of the Justice League and has been since the Heroic Age of theo 2010's era.