In hypothetical Northern secessions, usually AH writers either have the now Southern-dominated United States basically not caring that the North seceded and letting them go, or if the South does attempt to force the North back into the Union, the attempt fails and the North wins their independence. What I'm interested in is a scenario in which, for whatever reason, the North secedes and the South successfully defeats the North in an ensuing civil war, and in doing so the South basically has the ability to reconstruct (or deconstruct if you like) Northern society as it sees fit.
I'm open to what this Northern "confederacy" looks like, but I would say at the least it should contain the New England states and maybe New York and Pennsylvania.
So what would a Southern 'reconstruction' of the Yankees look like?
A situation in which New England and New York state would secede from the Union and New York City (under Mayor Wood) would then "secede from secession" and remain in the Union would almost be a Southerner's wet dream! If the Southerners and their "doughface" friends could win in this alt-1860 even *with* the "fanatics" of New England and Upstate New York in the Union, imagine their grip on power with those areas gone! President Breckinridge or Lane would *very* happily let these "erring sisters" depart...
Incidentally, consider Alexander Stephens' reaction to Lincoln's election in his speech to the Georgia legislature. It seems that both he and his listeners were not displeased by the thought of a Union without New England:
"My own opinion is, that if this course be pursued, and they are informed of the consequences of refusal, these States will recede, will repeal their nullifying acts; but if they should not, then let the consequences be with them, and the responsibility of the consequences rest upon them. Another thing that I would have that Convention do. Re-affirm the Georgia Platform with an additional plank in it. Let that plank be the fulfillment of these Constitutional obligations on the part of these States-- their repeal of these obnoxious laws as the condition of our remaining in the Union. Give them time to consider it, and I would ask all States South to do the same thing.
"I am for exhausting all that patriotism demands, before taking the last step. I would invite, therefore, South Carolina to a conference. I would ask the same of all the other Southern States, so that if the evil has got beyond our control, which God in his mercy grant may not be the case, we may not be divided among ourselves; (cheers) but if possible, secure the united cooperation of all the Southern States, and then in the face of the civilized world, we may justify our action, and, with the wrong all on the other side, we can appeal to the God of Battles, if it comes to that, to aid us in our cause. (Loud applause.) But do nothing, in which any portion of our people, may charge you with rash or hasty action. It is certainly a matter of great importance to tear this government asunder. You were not sent here for that purpose. I would wish the whole South to be united, if this is to be done; and I believe if we pursue the policy which I have indicated, this can be effected.
"In this way, our sister Southern States can be induced to act with us; and I have but little doubt, that the States of New York, and Pennsylvania, and Ohio, and the other Western States, will compel their Legislatures to recede from their hostile attitude, if the others do not. Then, with these, we would go on without New England, if she chose to stay out.
[A voice in the Assembly: `We will kick them out.']
[Mr. Stephens:] No. I would not kick them out. But if they chose to stay out they might...."
http://civilwarcauses.org/steph2.htm