Refer to the county by county electoral map of the USA as a guide for secession. When state by state secession starts there will be many red counties in blue states that will not want to be left behind in enemy territory. Why should pre-secession state boundaries apply any longer? Since the Constitution is now a dead letter any prior agreement established in accordance with its terms will no longer be in force. In the end, there will be isolated pockets of blue urban areas surrounded by a sea of red everywhere else. The cities will become untenable since they have no resource base to be sustainable, only large numbers of bummers, looters, and moochers waiting for their next welfare check.
The cities will become untenable since they have no resource base to be sustainable,
ah, but they do. Milking the suburbs for ‘local taxes’.
https://www.governing.com/archive/gov-local-income-taxes.html