The Charleston Mercury was the mouthpiece of the fire-eater Robert Barnwell Rhett. He was among the most radical of the southern disunionists.
Incorrect. The founding fathers declared their independence in three successive waves - the first being when a couple of colonies (and even some counties) asserted it for themselves in early 1776, followed by a majority declaration of the colonies as a whole on July 2, adopted July 4th, followed by a unanimous publication of the July 4th document in August upon the return of enough members from New York's declaration to sign the copy that appears today in the National Archives. The CSA followed the path of the first wave, with each state individually declaring its independence from the US. But since, unlike in 1776, they were splitting away from other states on the continent itself with the remainder choosing to stay put, a joint majority declaration of the states was unnecessary and a unanimous one would not have applied to the situation.
The Charleston Mercury was the mouthpiece of the fire-eater Robert Barnwell Rhett.
Yes, and as such it carried the secessionist message in its most direct form. Contrary to your claim, that message was revolutionary.