I’m with Dan on national divorce and wrote about it for Politico today:
The deleterious effects of a breakup would be enormous. A disaggregated United States would be instantly less powerful. Indeed, Russia and China would be delighted and presumably believe that we’d deserve to experience the equivalent of the crackup of the Soviet Union or the Qing dynasty, respectively. Among the catastrophes you wish on an adversary, secessionist movements potentially leading to civil conflict are high on the list.
The economic consequences could be severe. The United States of America is a sprawling, continentwide free trade zone, creating a vast domestic market that makes us all better off. Exchanging that for what might be a market Balkanized by state or region would be a major loss.
Finally, the United States foundering on its domestic divisions would be a significant blow to the prestige of liberal democracy. Abraham Lincoln worried about this effect the first time around, and it might be even worse now. This wouldn’t be a fledgling democracy unable to hold it together, but what had seemed a stable republic with the most durable political institutions on the planet.