Unsurprisingly, tempers are fraying as governments struggle to find ways to protect their own. The latest salvo was fired on June 23rd by America and the European Union, which complained to the World Trade Organisation (WTO) about China’s restrictions on the exports of nine minerals, including bauxite, coke, magnesium and manganese. These are important raw materials for the steel industry, among others, and China restricts their exports on the grounds that they are exhaustible resources. But America and the EU argue that by hindering their export, China is unfairly favouring domestic industries.

John Veroneau, a former American deputy trade representative, believes the case against China is a strong one. He also argues that this week’s move can be seen as an effort to foster more trade (as there surely would be if China were to ease its export restrictions) at a time when trade is in a great deal of trouble. In practice, it is unlikely to have that effect. If the case proceeds to the stage where a formal WTO panel is formed to decide on its merits, it could drag on for several years, by which time trade will, with luck, have recovered from its current moribund state.

Jeffrey Schott, a trade expert at the Peterson Institute for International Economics, a think-tank, says that the case against China may also help the cause of open trade in other ways. If Ron Kirk, America’s new trade representative, demonstrates that he is actively enforcing the agreements already in place, he may get “the authority to negotiate Doha and other accords”.

That may be too sanguine. True, America and the EU are not resorting to imposing fresh barriers of their own in this dispute; for that matter, China’s export restrictions are not new either. But trade experts warn that protectionism remains a serious worry. Of particular concern are the so-called “Buy China” requirements added to China’s stimulus package this month. These require recipients of money from China’s mammoth fiscal expansion to choose domestic suppliers “unless products or services cannot be obtained in reasonable commercial conditions in China”. This sounds like out-and-out protectionism. But America, which included similar “Buy America” provisions in its own stimulus bill, may find it hard to raise a stink.

© The Economist Newspaper Limited 2009