“The Americans get the toys, the Chinese get the Treasuries and we get screwed.” Thus a European Union official once characterised the pattern of Beijing accumulating US assets by selling renminbis for dollars, while nothing stood in the way of a rapid and destabilising appreciation of the euro.

It was this routine that led to the US running a huge current account deficit with counterpart surpluses in much of east Asia (including China) and parts of Europe, and among the oil exporters of the Middle East. A shift in exchange rates is almost certainly a necessary part of rebalancing the world economy, shifting the burden of consumption towards those surplus areas – a task that Ben Bernanke, Federal Reserve chairman, recently called “extraordinarily urgent”.

But as yet, there is little sign of either China or most east Asian countries (except Japan) allowing their currencies to appreciate substantially. And the recent experience of other emerging markets is likely to make them yet more reluctant.