It may only lead to a messy stalemate, but it does make quantitative easing a more dangerous and global contest.

The latest monetary manoeuvre is likely to have about the same effect on the Japanese economy as the many other fiscal and monetary efforts of the last two decades.

The aim is to stimulate growth and ward off deflation. But, as before, no noticeable change is likely. Despite the predictions of Keynesian economists, big Japanese deficits and near-zero interest rates have barely registered anything positive.

And despite the doom-laded predictions from the Austrian school, the mountains of debt and free money have not had any negative effects either.

The latest Japanese move was presented as a purely domestic stimulus. But the BoJ's target is more likely to be the US Federal Reserve.

The Fed said last week that it will be printing $40 billion, or about 0.3 percent of US GDP, every month. That amounts to an invitation to the currency markets to push down the dollar. So the BoJ has come back with a promise to print the equivalent of 0.2 percent of Japanese GDP every month in 2013.

The proposed countermeasure was enough to stop the yen's rise against the dollar, but only for a few hours. The intensifying international money-printing contest is dangerous because money printing seems to be distorting financial and commodity markets, even without any clear impact on economic confidence.

Even the cautious European Central Bank has said it might join in for the sake of the euro zone's troubled sovereign borrowers, although it promises to sterilise any newly injected cash.

Many countries are suffering the after-effects of the financial crisis. It would be much better for them to fight together rather than fight each other for the prize of having the weakest currency.