Id like to know when black people acquired sole title to the institution of slavery.
And of course there were no indentured servants, white slaves, in England or America right?
Indentured servitude was not slavery. It was neither perpetual nor hereditary. It was generally, though not always, voluntary.
In fact, it had more in common with the institution of apprenticeship than anything else. A period of some years of work in return for a start in life.
Let us not weaken our case by attempting weak arguments that are easily shot down.