Those who are calling for leaving this historic country today were the same people (well, descendants of), who were also making legislations to formalize the categorization of all blacks and their descendants of victims of slave trade as not equal with them, not humans but their property.
Human were considered and legally declared their property and they trade today in the name of human rights. How can they defendants of human rights? Have they cleared themselves of the historic taints of such savagery?
They still refuse to compensate the victims and their ancestors, while they compensated those who were owning slaves for the termination of their ownership of fellow humans.
This is the world we share with them, world is unjust and as such can't be sustained in its current order.