If, or rather, when the dollar fails (or we go into hyperinflation, ala Zimbabwe), debt might be a good thing to have... I'm thinking about acquiring some good debt... doubtful the debt would be indexed to the inflation, so 10K of debt could be paid off with 10K of money, that after hyperinflation would buy a loaf of bread... If wages kept up, in the black market, debts could be paid with pennies on the dollar...
If TEO arrives, I can imagine looking back fondly on the present tax collection system. A warlord, or what have you, will collect more valuable things than money... they will BE paid... be it with the food you need for your own survival, your livestock, or your excess family members. Don't worry about cash... you'll always have something of value to those who are more powerful... of course, you might not cotton to slavery for yourself or your family, but as a slave, you still might eat on a semi regular basis.
If I were a "tax collector", 'warlord' or what have you, I wouldn't take your greenbacks... (toilet paper would probably have a higher value) and unless society had progressed beyond simple survival, I wouldn't take gold or silver... I'd take your food first, then able bodied humans... probably not on a regular basis, but for several weeks in the spring and fall, during planting and harvest times, and at other times for public works projects...