disintegration theory: one thing that distinguishes the united states from other countries is the ease with which we can decentralize on the fly. If the federal government were to collapse, the state governments would be ready and willing to keep their state a capital-S State. If the state government falls, counties have such tight ties that they would start rebuilding trade without the need for a state to intervene, and the counties are so stable in most places that you wouldn't have to get to the last stage -- but the last stage is the apocryphal Gun Behind Every Blade of Grass.