This is of course like the ENRON Scenario. . .except for the collapse of a country one can see it coming, like happened more or less in Zimbabwe not so long ago. . .the old ZIM $ was completely taken out as it became worthless and they created a new currency. . .I even forgot wat it is called. Somehow I do not think it is the US $ they use now.
In El Salvador they switched to the US Dollar some years ago as the Colones were eliminated although there the currency did not colla[pse to near zero as happend in Zimbababwe.