Athenian owls, Roman denarii, British sovereigns, US dollars. There have been many pseudo reserve currencies down the ages. Now the governor of the People's Bank of China has called for a new global currency “disconnected from individual nations”. Russia, too, wants to move away from a world dominated by the dollar. Kazakh president Nursultan Nazarbayev suggests such a currency could be called the acmetal – an amalgam of “acme” and “capital.”
But is there a case for one? In theory, yes. (Although no one was banging the table for change when emerging growth rates were still being powered by deliberately undervalued domestic currencies.) The reserve currency status of the dollar helped to create nasty global imbalances – one of the main culprits of the current downturn. As China, for example, recycled export earnings back into dollar denominated assets, the US could happily run profligate trade deficits with impunity. That helped push up the price of US assets, particularly house prices.
Now surplus countries are stuck. They cannot diversify fast enough and a rapid sell down of US assets would destroy their portfolios. Not only that, global central banks holding about two thirds of their reserves in dollars are hostage to the Obama administration. Unsurprisingly, huge budget deficits and the Federal Reserve's leap into quantitative easing have foreigners fretting over the longer term health of the dollar.