If cash disappears, what would happen in a national emergency?

We discussed the cashless society today on the show. A caller asked what would happen in a national emergency if the grid went down in a cashless society?

Our guest David Wolman said that this scenario is one of the top arguments in favor of hard currency, but there are systems that would work:

In the late 60s in Ireland, they had a banking strike and everyone thought commerce would grind to a halt because there was no money about with which to perform exchanges. The reality is that people started scribbling these handwritten IOUs and they served the purpose of currency just fine. As long as the people believe the thing has value, it can work as a form of money. If the disaster scenario is the last strong case for cash, then maybe we could find an end-around.”

Wolman added that Tide detergent has been used as a currency in the Minneapolis drug trade and canned mackerel has been used as cash in prisons.

mackerel.jpg (Horse mackerels are displayed at a supermarket in Tokyo on April 5, 2011. YOSHIKAZU TSUNO/AFP/Getty Images)

–Stephanie Curtis, social media host