Let us see if we can at least agree on what the Constitution itself says.
No Person held to Service or Labour in one State, under the Laws thereof, escaping into another, shall, in Consequence of any Law or Regulation therein, be discharged from such Service or Labour, but shall be delivered up on Claim of the Party to whom such Service or Labour may be due.
I understand this to mean that no state can pass a law depriving a man "from such service or labour" as he is legally due.
Meaning that going to another state will not free a slave from the labor he owes to whomever has the legal right to his labor.
Do you understand this to mean something different?
So, you not only justify slavery in the South, you also deny the constitutuional right of Northern states to abolish slavery within their own boundaries?
What we know for certain is that Northern states began abolishing slavery in 1777, and by the time of the Constitutional Convention in 1787, all but New York and New Jersey had passed such laws.
So, there's no suggestion from our Founders that slavery could not be abolished by states which didn't want it.
Indeed, all indications are the opposite -- slavery was in those days expected to be abolished, gradually, lawfully, even in the South.
That's what abolishing international imports of new slaves was all about.
Fugitive Slave provisions were understood to mean just that: when runaway slaves were captured, they must be returned to their "owners" -- it certainly did not mean that Southern tobacco farmers could bring their slaves north to grow tobacco in, say, Pennsylvania.
So, Tanney and now you are providing a Constitutional interpretation which was and is firmly rejected by scholars, historians and absolutely rejected by Northern voters in 1860.
I understand this to mean that no state can pass a law depriving a man "from such service or labour" as he is legally due.
Meaning that going to another state will not free a slave from the labor he owes to whomever has the legal right to his labor. Do you understand this to mean something different?
Tsk. Tsk. This is your argument that the Constitution forced all States to "embrace slavery" (as Davis did)? Let me put the Article in terms that maybe you can understand.
"No owned Slave from a Slave State, escaping from his owner into a Free State, is then considered Free, but rather must be returned to his owner in the Slave State."
You see, the article is about the Slave and the recognition of the rights of Slave States by Free States. Article IV is not about the owner of the slave. The owner must remain in the Slave State. That owner was not allowed to bring his Slave into a Free State. Nothing in the Constitution says that all States must "embrace slavery".