Supreme power (of the federal government) was intentionally not made part of the Constitution because it would have never been ratified otherwise.
Slavery was not specifically cited in the Constitution for similar reason.
"Slavery in the territories" had been a federal power since the Northwest Ordinance which predated the Constitution. The issue was how, and therefore which, territories.
Taxation and allocation of the income from taxes were provided for in the Constitution and the south believed that both taxes and trade tariffs were being applied unfairly and to the detriment of agricultural (slave) states.
When South Carolina left the union, leaving a federal fort blocking Charleston harbor to be resolved, they hoped for the arrival of troop ships to remove that federal presence.
Instead, they got resupply ships enabling the union to retrench and remain.
SC considered that resupply as a use of force and intention to remain by threat of force and if force is legitimate to stop secession, then force is equally legitimate to bring secession about.
When they fired on one of those ships, and Sumter, they had no thought of treason because they held the union to have been dissolved by the act of secession.
The right to secede was then a 50/50 proposition and deciding that issue was the true cause for the unlimited extent and carnage of that war.
"Treason" became an accepted stigma as a means of sustaining adequate support for the war in the north.
It can readily be argued that northern abolitionists "caused" the war by limiting any president's ability to negotiate or conciliate, by encouraging revolt within the South, and by inflaming Northern emotions.
Since talk of secession is once again making the news here in the US, some here might want to reconsider their hard line beliefs regarding the war between North and South.
As to the question in #9:
I doubt such a deal was possible in 1861 but, given Sherman, Reconstruction, and the fact that this side of East Texas there was little geography that would be hospitable to a slave economy, I'd certainly rather they could have pulled it off by peaceful means a decade or so later.
Finally, Ron Paul and Chuck DeVore are both idiots.
You might want to reexamine that argument.
A parallel one would be to say, "If force is legitimate to prevent a bank robbery, then it is equally legitimate in perpetrating the robbery."
Force is legitimate, when other options fail, in defense of rights and in the service of good. It is never legitimate in the furtherance of evil or the violation of rights.