Currencies are controlled by politicians and central bankers and do compete with each other. It's called currency manipulation.
I think you are being extremely naive if you underestimate the control that politicians and central bankers exert over the economy. In a fair free market economy...
Hi Capablanca:
You are making the assumption that fiat money is superior to a commodity money as a medium of exchange, but I don't see the evidence to support such a conclusion. In the late 1800's, the US economy was expanding and productivity was up yet prices were actually falling. That is...