Morals are subjective, nay they don't even exist. If slavery came back tomorrow, there is nothing anybody can say to categorically dismiss it. What is objective though is that humans are cruel. This may not justify cruelty, but surely a healthy person (unlike black people who say racism is wrong yet hate white people based on past "atrocities" lol...) realises how people get on/behave.
I personally don't give a shit about "atrocities", as stated people are cruel and it's in our nature to be so.
I personally don't give a shit about "atrocities", as stated people are cruel and it's in our nature to be so.