While secession of American states is often dismissed as absurd, there are few reasons to believe that a state like Texas - to name just one example - could not immediately transition from state to nation-state.You're missing the only thing that matters. Raw force. Brussels doesn't have nukes. DC does have nukes. DC has repeatedly shown an instant readiness to use all necessary force to squash every hint of secession. Unless a coalition of states containing missile sites can QUICKLY take over all the missile sites, there's no point in thinking about secession.