They are so screwed.
I posted this on their comment thread. The key point is that FEMA and all of the govt’s resources can only “rescue” one or two Katrinas at a given time. If an entire region loses power even for one week, store looting will evolve into truck hijacking and then to blood in the streets as gangs fight for control of the remaining resources. At that point it won’t be a matter of flipping the power back on, society will be gravely and perhaps fatally wounded once every fuel and food truck runs out of diesel, comes to a stop, and is looted. Once the trucks stop moving, society goes immediately into starvation mode, then panic and anarchy. Read my new short story floating around the internet called “Alas, Brave New Babylon” for one take on this type of collapse scenario.