Interesting with the media pushing this Obama/Lincoln meme, that the states like Miss, AL, LA, GA, SCar have large black populations as a percentage. So if those states secede, or tried to secede, the next move would be to paint the move as a return to the 1950s or slavery, and it would be contested on those grounds as a threat to civil rights.
That, of course, is absurd, but it is what would happen, then the world would be given a portrayal of the entire thing as a move by the Racist South and West to return to segregation.
I bring this up as a form of 3 Dimensional chess...knowing this is how it would be framed before it happens means to take that into account.