"Backed" is a term that everyone throws around. I don't understand how a money needs backing. For instance the properties of gold made it money, not some sort of trust consortium. Money is trusted the way gravity is trusted. It IS the thing. I guess having the knowledge of physical reality predisposes you to trust it but that's as close as you can get to a tautology without repeating words. Fiat needs trust precisely BECAUSE it doesn't comport with reality.