The most overlooked cause of the economic weakness in the US and Europe is what we call the “global currency wars”. If all currency intervention were to cease, we estimate that the US trade deficit would fall by $150bn-$300bn, or 1-2 per cent of gross domestic product. Between 1m and 2m jobs would be created. The eurozone would gain by a lesser but still substantial amount. Countries that were engaged in intervention could offset the impact on their economies by expanding domestic demand.

China is by far the largest currency aggressor but has not been the major perpetrator of late. Three distinct groups are now involved. First are other Asian countries, including Japan, Singapore, Taiwan, Korea, Hong Kong, Thailand and Malaysia. Second are major oil exporters including the United Arab Emirates, Russia, Norway, Saudi Arabia, Kuwait and Algeria. Third are rich countries near to the eurozone, most notably Switzerland but also Denmark and Israel. If Mitt Romney is elected US president, he will be able to label many countries as currency manipulators on his first day in the Oval Office, not just China, as he has promised.

These countries all exhibit rapidly growing levels of foreign currency reserves as well as significant current-account surpluses. They buy US dollars and euros to suppress the value of their own currencies, keeping the price of their exports down and the cost of their imports up. Thus they subsidise exports and tax imports, enabling them to maintain or increase trade surpluses and pile up foreign exchange reserves. These tactics, in effect, export unemployment to the rest of the world. China has largely curtailed its currency aggression, at least for now, but many other countries remain highly active.