A country's exchange rate cannot be a concern for it alone, since it must also affect its trading partners. But this is particularly true for big economies. So, whether China likes it or not, its heavily managed exchange rate regime is a legitimate concern of its trading partners. Its exports are now larger than those of any other country. The liberty of insignificance has vanished.

Naturally, the Chinese resent the pressure. At the conclusion of a European Union-China summit in Nanjing last week, Wen Jiabao, the Chinese premier, complained about demands for Beijing to allow its currency to appreciate. He protested that “some countries on the one hand want the renminbi to appreciate, but on the other hand engage in brazen trade protectionism against China. This is unfair. Their measures are a restriction on China's development.” The premier also repeated the traditional mantra: “We will maintain the stability of the renminbi at a reasonable and balanced level.”

We can make four obvious replies to Mr Wen. First, whatever the Chinese may feel, the degree of protectionism directed at their exports has been astonishingly small, given the depth of the recession. Second, the policy of keeping the exchange rate down is equivalent to an export subsidy and tariff, at a uniform rate – in other words, to protectionism. Third, having accumulated $2,273bn in foreign currency reserves by September, China has kept its exchange rate down, to a degree unmatched in world economic history. Finally, China has, as a result, distorted its own economy and that of the rest of the world. Its real exchange rate is, for example, no higher than in early 1998 and has depreciated by 12 per cent over the past seven months, even though China has the world's fastest-growing economy and largest current account surplus.