“They need to remember that no large city can supply its own power water or food. It wouldn’t be force on Force, it would be asymmetric”
It would be red states vs blue states The forces would be what military bases and resources are in the respective states that Governors can maintain control.
I would think that *some* state governments would respond at the state level, yet within some states majority blue (driven by large metro areas such as LA/San Fran/ NYC/Chicago) the red areas would act, well ... red ... independently. Same for ‘blue’ cities in red states. It’ll come down to zipcodes and road ‘barriers’ like the 285 loop around Atlanta.
Cities/metros that at odds with the surrounding region will face loss of utilities and resupply by truck and train.
A good reference to drive conversation is this: https://diamondbacksol.com/bracken-when-the-music-stops-how-americas-cities-may-explode-in-violence/
Your opinions may vary of course.
WHEN IT is over-—I WOULD EXPECT TEXAS TO SECEDE-—and many states to go with them.