[Polybius]

You are dancing around the central point.

Only if you define "The Central Point" as "Totally Ignoring the Clear Language of the Tenth Amendment".

Again, secession is nothing other than the declaration that the state legislature's acts, and not the Constitution, are the supreme law of the land.

Only if you totally ignore the clear language of the Tenth Amendment.

You cannot have secession without directly violating the supremacy clause of the US Constitution.

Only if you totally ignore the clear language of the Tenth Amendment.

Was secession mentioned in the Constiturtion?

No.

In 1860, had there ever a Federal law passed that mentioned secession?

No.

What did the Constitution say about the powers not specifically prohibited by the Constitution or prohibited by Federal law?

[wideawake]

Jurisdictional supremacy is one of the powers expressly delegated to the federal government by the Constitution.

So the Tenth Amendment, by its own language, does not permit any state to claim jurisdictional supremacy.

Secession is nothing other but a declaration by the seceding entity of its own jurisdictional supremacy - a violation of Article VI of the Constitution and a claim of power that is expressly excluded from the scope of the Tenth Amendment.