The US dollar is expected to plummet big time over the next six months with Goldman Sachs warning that teh dollar is likely to fall further over the next six months. It says the Canadian dollar will reach parity and the Aussie will come close to it, although it sees a recovery 12 months out from now.

The question is what that means for the US dollar as a global reserve currency. The Economist makes the point that there are no simple solutions but says the state of the greenback highlights the parlous state of the US economy.

The Economist writes: "A country heavily in debt to foreigners, with a government deficit it is making little headway at controlling, is creating vast amounts of additional currency. Yet it is allowed to get away with very low interest rates. Eventually such an arrangement must surely break down, bringing a new currency system into being, just as Bretton Woods emerged in the 1940s."

This doesn't mean the dollar will lose its reserve currency status. There simply aren't that many alternatives. But it might be different if foreign creditors tell the Americans start issuing debt in other currencies.

And given the state of the US economy now, America won't have that much bargaining power, not with a bunch of foreigners taking US debt, and potentially holding various administrations to ransom.