[capitan_refugio]

I am afraid you are becoming entangled in technicalities. Unilateral secession is a declaration of war because it is revolutionary and must be defended by armed conflict.

[Non-Sequitur]

Unilateral secession is a declaration of war because it is revolutionary and must be defended by armed conflict.

I don't want to get bogged down in technicalities but I can't see using terms like 'declaration of war' in this case. War is conducted between sovereign nations and the confederacy wasn't one. First to last the Civil War was a rebellion initiated by the southern states and waged against the lawful government in Washington, D.C.