Indeed it's the only thing that ever has. Margaret Mead Turkey killed 1.5 million Armenians in the early part of the 1900's. Nazi Germany killed 6 million people in the 1940's. Khmer Rouge killed over 1 million in the 1970's. Rwanda killed 1 million people in 100 days.
Great leaders are principle-center.
They have vision. They inspire, motivate. They have good people skills. They work to break negative cycles, take action, and impact community. They value diversity.