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Legally these would be Apprentices of a guild or a union, indentured servants and debtors working off a debt through service to those that loaned them the money, not slaves."
You are simply WRONG.
http://caselaw.lp.findlaw.com/data/constitution/article04/15.html#1
"This clause contemplated the existence of a positive unqualified right on the part of the owner of a slave which no state law could in any way regulate, control, or restrain. Consequently the owner of a slave had the same right to seize and repossess him in another State, as the local laws of his own State conferred upon him, and a state law which penalized such seizure was held unconstitutional. Congress had the power and the duty, which it exercised by the Act of February 12, 1793, to carry into effect the rights given by this section, and the States had no concurrent power to legislate on the subject. However, a state statute providing a penalty for harboring a fugitive slave was held not to conflict with this clause since it did not affect the right or remedy either of the master or the slave; by it the State simply prescribed a rule of conduct for its own citizens in the exercise of its police power."
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I challenge you to provide a legitimate opposing resource.
I've already given a Founding Father who would have been considered a perfect case for
Article IV Section 2 as I have described it: Ben Franklin, who as an apprentice printer ran away from his master to which he had been legally bond to learn the craft during a period of labor or service.
And summit to you the actual writing of an indentured servant describing the conditions by which they had to live under, the only difference between them and slaves, a legal contract that would expire when all conditions were met by the servant.
After reading such an account how is it any different from a similar account of life aboard a slave ship?
Legally Defining slavery vs servitude (Debtors, Apprentices, and Indentured Servants) is the missing link in this argument.
Those of us blessed with the passage of time tend to forget that indentured servants even existed in a time where a female one was subject to on average of 12 lashing with a whip or 240 extra days added to her contract for getting pregnant by her master as well as possibly an additional 2 years of service under the charge of "the churchwardens of the parish where she lived" according to the laws of Virgina.
but of course I'm "wrong" when I point out that the labour and service described in Article IV Section 2 describes a legal relationship between apprentices of a guild or a union, indentured servants and debtors and those to which they had bound themselves voluntarily and legally, how soon we forget the hardships and cost that went into building this country and the price paid by those that did.