Reading the hysterical, lawyer like responses that attempt to disprove the essential premise: the Delcaration of Independence is a secessionist document, demonstrates that we are winning in the marketplace of ideas.
You are correct. It is a Secessionist Document. However, The Difference between Secession and Treason, was
Victory on the Battlefield SOmething the South wqs unable to attain.
Further, The Long List of usurpations, in the DOI, since you are content to vouch for it's legitimacy, is hardly matched by the 'We don't like this game, so we are taking our ball and going home' treason movement, as practiced by the Confederacy.
Article 1 Section 10 Clause 1 was quite clear.