How in the world could we ever get back to a hard currency anyhow? The whole economic system of the planet is based on fiat money and central banks.
Is there even enough gold and silver to cover all the paper and credit?
I'll try to make this simple: bear with me -
In the 30's, the worst traitor to ever be president since Lincoln, FDR, not only took us off the gold standard, but confiscated all privately held gold except jewelry - and then turned around and sold it on the international markets for more than he paid for it in paper "dollars". However, the COINS were still silver. Without out gold backing, the money could be inflated...but only up to the point that weight of $1.00 in coins didn't contain more than $1.00 in silver. If the weight of the coins in silver was more, (say, $1.50...), you could get change for a paper dollar, melt it down, get $1.50, etc, and soon there would be no coins. This is part of why the very wise Founding Fathers mandated that ONLY gold or silver coin would be money, and that ONLY Congress would coin money and set the exchange rates between metals. This is also an example of "Gresham's law", which says that any circulating currency consisting of both "good" and "bad" money (both forms required to be accepted at equal value under legal tender law) quickly becomes dominated by the "bad" money. This is because people spending money will hand over the "bad" coins rather than the "good" ones, keeping the "good" ones for themselves. (Seen any silver coins in your pocket change? REAL silver, that is? Now you know why... This is also why, in the old East Germany, where by law East German marks had the same "value" as west german ones, when they actually traded at 8 to 1, almost no one ever spent western currency.).
So because coins were silver, the "dollar", which before had been pegged as being 1/20.67 ounce (1.5048 g) of gold, now oculd be inflated (more "money" cranked off of the printing presses chasing the same pool of goods and services) until a silver dollar contained more than $1.00 worth of silver...which happened in 1964.
So the governement stopped using silver in coins. They basically made their new coins out of worthless sandwich slugs of a nickle-copper-nickle sandwich. This put us, de-facto, on the "copper standard", until...
The weight of 100 pennies held more than $1.00 worth of copper. Remember the era of copper thefts in the late '70s - early '80s, when people would steal wiring and plumbing, and burger joints would give you a free hamburger if you changed in a roll of pennies, or 3 burgers would sell for two rolls of pennies? This was proof that the US had inflated its currency to the point where we could no longer even stay on the COPPER standard! The penny was switched to a zinc slug with a thin coat od copper - (cut a new penny in half & see for yourself!) in 1982.
Now, our worthless, illegal fiat money has been inflated to the point that we will have to go off of the "zinc standard" - and coincidentaly, China and Opec are about to stop doing business in dollars. Gee I wonder why? Fact is, when you inflate a currency by cranking the presses, you basically steal worth from EVERYONE that is holding the inflated currency - all without pass and collect taxes, etc. You can pick the pockets of the whole world from the comfort and privacy of your office.
Now, if the currency WAS pegged to a precious metal, I'm sure there would be more than enough gold, silver, brass, copper, zinc, platinum, etc to go around...you just set the par value low enough.