James Madison had strong views on whether the Congress had any constitutional authority to pass laws concerning the new territories:
Congress has undertaken to do more: they have proceeded to form new states, to erect temporary governments, to appoint officers for them, and to proscribe the conditions on which new states shall be admitted to the confederacy. All this has been done; without the least color of constitutional authority
(Federalist #38)
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The Missouri Compromise of 1820 was ruled unconstitutional in Dred Scott. Chief Justice Taney said Congress did not have the authority to restrict slavery in any territories. Slaves were property, and the restriction of property without due process violated the Fifth Amendment of the Constitution.
In Strader v. Graham (1851), for example, the Supreme Court ruled that the Ordinance was no longer in force in the states formed in the northwest territory.
Many of your arguments are a rehash of material already covered by NS. Please see post #65.
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why was it that South Carolina should care so much about what happened in territories a 1000 miles away?
Because the government used the excuse of the 'Compromise' to prevent States from deciding whether or not they would be slave-holding States. If all the territories that became States were allowed to maintain the slave holding status they had had all along, there would have been more slave holding than non-slaveholding States.
The federal government was "Stacking the deck?" in an effort to restrict something they legally had no say in.
In Strader v. Graham (1851), for example, the Supreme Court ruled that the Ordinance was no longer in force in the states formed in the northwest territory.
It is very true that by 1851, the Northwest Ordinance was not in force. The land that was Federal territory in 1789 was then all independent states, admitted to the Union with all the privileges (and duties) of the original states. Their applications for statehood and constitutions had been reviewed and approved by Congress and they were granted statehood.
But if the very law that allowed them to organize was found unconstitutional long after the fact, the logical conclusion from the Court should have been that the Constitutions of those states that outlawed, by requirement of Congress, that particular brand of property (slavery) were violations of the Federal Constitution. Their Constitutions should have been overturned. But Taney and the majority never suggested that. Why?
And what of the original thirteen states? Did Pennsylvania, for instance, (which outlawed slavery a nearly a decade before before the US Constitution was enacted) be required to allow slavery? It was a "free state" when it entered the Union under the Constitution. If new states are given the same rights as the original states, are the original states given the same as new states? Was Pennsylvania required to allow slaves to be imported from other states under the 1851 decision?
If the Taney decision was right, then the reading of the Constution was that the right to own slaves must exist in every state and no state could ban it.
It takes a very strange view of the Constitution to come to that conclusion. As to original intent of the Framers concerning slavery in the territories, I'd refer you to Lincoln's Cooper Union Address.
The federal government was "Stacking the deck?" in an effort to restrict something they legally had no say in.
Seems to me that the Slave Power were the prople "stacking the deck" by mangling beyond recognition the intent of the Framers. But they had already repudiated the Declaration. Twisting the constitution into knots was a logical next step.