What was worse? Slavery in America or the Holocaust?

What do you mean by "worse" Do you mean qualitative moral evil? Qualitatively fewer people were killed in the holocaust than in the Atlantic slave trade and the Atlantic slave trade continued for centuries, while the Holocaust really (in the sense of deliberate extermination) lasted only four years from 1941 to 1945. But the intensity of the slaughter in the holocaust is correspondingly greater. In each case, death and suffering were institutionalised in a political and economic system, and normalised and justified for many ordinary people as a necessary part of life. It's very hard to choose which was "worse" - in many regards they were very similar. If I had to decide, I would say slavery was perhaps more repugnant, because it was part of an economic system which made Europeans wealthy on the backs and bodies of African slaves, with the collaboration of Africans. The Holocaust was also justified by extreme racism, but the m-slaughter of Jews in extermination camps was the result of wartime expediency, when Germany's leaders argued they had no other option but a "final solution to the Jewish question."