a long time ago when Pat Frank wrote the first modern post apocalyptic novel Alas Babylon, he described official martial law as including the suspension of all debts owed -like mortgages.
not sure that would happen today. martial law law would likely come in a 2800 oage document pre-written that no one has read but is rapidly signed into law.
I think if I was in Cleveland and chaos happened, that's what I'd do....walk away.