the first to be blame is the African , they accept to sell black prisoner to the black-market of slave , As I know for my Island Mauritius 300 yrs ago ,
The current version of slavery is the illegal immigrant, and the politicians who ensure the practice continues are the current slave traders. They push to get them here, knowing they can't find legal employment, so they become landscapers and migrant farmers, working without a minimum wage, making whatever they can get. They don't get any medical or retirement plans. And the government continues these policies because 'they take jobs no American wants'. How is that NOT slavery, and those who take their labor are simply profiting off their inability to obtain citizenship by legal means. So long as we continue open border policies, slavery will continue.
valuing national image more then quality of life. this began waaay back around the time of agriculture becoming more or less universal. tens of thousand of years ago. also narcissism and ego of everyone who imagines these things to be natural and innocent. who's to blame for it continuing, wither overt or covert, are people who believe in the fantasy that people who look and think like themselves are somehow superior to anyone who does not.