I will point out that the Declaration of Independence is not the supreme law of the land. The Constitution, and the laws and treaties made under it, is.
You are really talking in circles and repeating yourself w/o responding directly to the issue at hand.
All rebellions, ours included, are deemed illegal by the governing authority and then deemed to be either justified or criminal by the victor.
Such is the case here. The Colonists deemed the repressive regime of the British to be such that they justified a rebellion by declaring issues and rights that previously did not exist, consent of the governed being one.
The Colonists are praised for their heroism, judgment and righteousness. But how did they differ from the Confederates, who essentially followed the same guidelines and principles established a mere 80-90 years earlier?
Recall, slavery was Constitutional, so one cannot condemn them for defending their Constitutional rights, while simultaneously arguing that the Consitution is the Supreme Law of the land, and then use that argument to deny them their Rights.