...in a few small, walled towns

Roberts warned that the potential destruction of the dollar as the world's reserve currency could eventually return us to a system of barter, completely altering the landscape of the economic structure as we know it.

...with a short period of gold and silver
as currency in between, I expect.

Barter could only be avoided if enough
people used the "hard" currencies. Perhaps
for a while. Then their prices go so high,
(relative to trashed currencies) nobody's
buying or selling them, only using them.

That's only one possibility.

We must think of human progress, not as of something going on in the race in general, but as of something going on in a small minority, perpetually beleaguered in a few walled towns. Now and then the horde of barbarians outside breaks through, and we have an armed effort to halt the process. That is, we have a Reformation, a French Revolution, a war for democracy, a Great Awakening. The minority is decimated and driven to cover. But a few survive - and a few are enough to carry on.
--H. L. Mencken

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