[lentulusgracchus]

Concerning definitions, since you doubt me, here are a couple I dredged up using the dictionary on Findlaw:

sovereign
Variants: also sovran

1: possessed of supreme power
Example: a {h,2}sovereign ruler

2: enjoying autonomy
Example: {h,2}sovereign states

3: relating to, characteristic of, or befitting a sovereign

sovereignty
Variants:also sovranty ['sä-vren-te, 'se-, -ve-ren-]

pl: -ties

1 a: supreme power esp. over a body politic

b: freedom from external control: "autonomy"

2: one that is sovereign

esp
: an autonomous state

dual sovereignty doctrine
: a doctrine holding that more than one sovereign (as a state government and the federal government) may prosecute an individual without violating the prohibition against double jeopardy if the individual's act breaks the laws of each sovereignty

Just so you can't hold forth that I'm pulling all these words out of my......wig.

[Frumious Bandersnatch]

sovereignty
Variants:also sovranty ['sä-vren-te, 'se-, -ve-ren-] pl: -ties

1 a: supreme power esp. over a body politic
b: freedom from external control: "autonomy"

2: one that is sovereign esp : an autonomous state

Very good.  Still makes my point.  None of the southern states were autonomous states, free from external control or had supreme control over the body politic.  IOW, they weren't sovereign.  Sovereign and supreme are still synonyms.