You know that even Columbus' contemporaries condemned him, right?
Columbus’ cruelty was recognized in his own day. Spanish churchmen condemned him for carrying off women from their husbands and subjecting them to the pleasures of other men. Friar Bartolomeo de las Casas, who accompanied Columbus on his third voyage, wrote, “The silence.” His published accounts included contemporary illustrations of native mothers drowning their children to save them from Spanish cruelty.
Also not true. You'll need to be more specific. Every individual person has not committed atrocities and neither has every group of people. Once you start getting into governments of countries you might be getting somewhere.