Is the US Dollar Backed by Gold?

Mainstream economics acknowledges that the US dollar has not been backed by gold since President Nixon ended the Bretton Woods system in 1971. However, conventional theory often struggles to clearly explain what backs fiat currency, sometimes suggesting it's backed by 'faith and credit' of the government, the strength of the economy, or the government's ability to tax. Many mainstream economists focus on the Federal Reserve's role in managing money supply and maintaining price stability, but don't always articulate the fundamental operational realities of how modern fiat money actually works.

MMT explains that the US dollar is not backed by gold, nor does it need to be. Since 1971, the dollar has been a fiat currency backed by the tax obligation itself. As Warren Mosler and other MMT scholars demonstrate, taxes create demand for the currency by requiring citizens to obtain dollars to meet their tax obligations to the government. This tax-driven demand gives the currency its value and acceptance, not gold reserves or any other commodity backing. The government's monopoly power to issue the currency, combined with the legal requirement that taxes be paid in that currency, creates the necessary and sufficient backing for fiat money. L. Randall Wray emphasizes that this understanding reveals how the currency issuer (the federal government) operates differently from currency users - it doesn't need to 'find' dollars to spend because it creates them through spending. The real constraint on government spending is not running out of money (which is impossible for a currency issuer), but rather the availability of real resources and the risk of inflation if spending exceeds the economy's productive capacity.