The Southern states indeed considered disunion necessary.
Of course, they did, but it was, factually, all a pack of lies and nonsense which nobody who was not 100% committed to the Southern slavocracy accepted or recognized.
Well, yes, there were a few, here and there, Charles Dickens comes to mind -- he was so embittered and angry at Northerners for having copied and sold his books without paying royalties, that he was happy to employ Southern lies & nonsense against the Union cause.
And the English aristocracy, generally, recognized kindred spirits in the Southern slavocracy.
So Confederates were not without sympathizers, but no major government and no majorities anywhere bought into Confederate propaganda.