I am a preper. Have a years supply of long term storage food, silver, and wine stored up in case of emergencies. When the soviet union broke apart, I've read they relied on the bartering system to obtain necessities and the 'currency' to use to barter with was fuel, cigarettes and liquor. I doubt many had gold or silver. But this is my 'emergency' stash. One never knows in todays World. Look at our modern society. How reliant we are on electronics for our everyday financial transactions. 'Money' seldom changes hands, it's either debit or credit card. We have an Open Skies Policy, meaning planes from other nations can fly over our nation by merely letting us know they are doing it. Now imagine an Iranian, or other 'unfriendly' flying a plane over and detonating a strong EMP (Electromagnetic Pulse) over the heart of America; or an exceptionally strong flare from the sun while the sun is directly overhead the USA. It would take out every microprocessor in the nation. Cars wouldn't run, banks would be down, computers, the stock market, everything that has a microchip! (The military hardware is shielded thankfully) How would we function? The only way is by having a real currency you can hold in your hand that is valued by the seller. I pray we never see that day, but it's better to be prepared than be caught with your pants down. I believe the Worlds economies and monetary systems are too intertwined for one to take down the other. But there has been repeated economic/monetary emergencies in the past, and history always repeats itself.