"Peace-maker Die" Paradox (Thank you, Extreme)

A person of peace comes along, fighting injustice and changing the world in his or her time. The person's life ends violently, either having to sacrifice his life to save the universe or victim of assassination/unjust death penalty sentence. Meanwhile, tyrants either remain in power until they die, or they rot away in exile or prison, never fully receiving the punishment they deserve. In either case, they live passed the average human life span.