The brewing trade battle over GM crops will cost America dear, say Victor and Runge

America's farm lobbyists have long been pressing their government to launch a formal trade dispute against the European Union's ban on genetically modified crops. This week they got their way, as the US and more than a dozen allies started proceedings within the World Trade Organisation.

For US farmers - the world's top planters of GM crops - the case is a welcome chance to crack open a lucrative market. But the case may ultimately do their country more harm than good.

Now is a particularly bad time to embark on a dispute that will inflame anti-Americanism in Europe. In the broader, already deteriorating relationship with continental Europe, the US has much more important issues at stake, notably reviving the Doha round on trade and mending diplomatic relationships strained by the Iraq war. Moreover, a close look at the options reveals that each of the plausible outcomes from a dispute would leave the US worse off than before.

First, the US could pay the political costs of launching an inflammatory dispute and then lose. Most press accounts compare this case with one of the first disputes ever handled by the WTO: the EU's ban on beef that had been produced using hormones. The EU lost because its ban had no basis in science and in "comparable" areas of food policy it had adopted much less strict rules - a telltale sign that the ban was a protectionist gambit.

On the surface, the cases appear similar. Although the science on the health risks of GM food is contested, essentially all the credible evidence shows that these foods are safe, which would seem to indict the EU ban. But in critical ways the cases differ. Across the board, the EU is tightening food safety regulations in ways that seem irrational by standard cost/benefit tests but, crucially, are broadly non-discriminatory and consistent - the key tests for whether a trade ban is legitimate. Moreover, the GM ban is a temporary measure - unlike the permanent ban on beef hormones - and trade rules allow more flexibility for countries that implement temporary measures when they can claim the science is uncertain.

Second, the EU could change its rules in the middle of the dispute. For several years, EU bureaucrats have been designing a new set of standards that would "reopen" Europe's markets to GM foods if traders complied with onerous tracing and labelling requirements. This shift would make it harder for the US to win because trade laws are tolerant of labels that allow consumers to make the final choice. While the US might respond by dropping the suit, it would be more likely to redirect the dispute against the tracing and labelling rules. In the past, hotly contested trade disputes have usually taken on a myopic life of their own. Each side digs in and the political damage spreads.

Third is the most likely (and worst) outcome: the US could win. The victory would be Pyrrhic because the issues are fundamentally ones of morality and technology - they must be settled in the courts of consumer opinion. On this score, the beef hormones case is instructive. Even today, hormone-treated beef is no more able to find European consumers than it was before the US won its case; and the years of legal wrangling have led to counter-sanctions that have harmed a wide variety of unrelated products and industries. The antagonism over GM foods appears to be unfolding in much the same way.

A better strategy would have been to stay the course that US policy has followed ever since the controversy over GM crops broke out in the late 1990s. Time is on America's side because the technology is already proving itself in the marketplace and European opponents will find themselves increasingly isolated.

But now that Washington has pulled the trigger, what can be done? The greatest danger is that both sides of the Atlantic slide into a tit-for-tat retaliation. But a trade war will cause untold harm to an alliance already in stress and make it harder to rejuvenate the soggy world economy. Cooler heads must prevail.

In Europe, the critical need is to reform the moratorium on GM foods. Frustration over its inability to get the import ban lifted is what pushed Washington to this desperate act. In the US, serious movement in Europe must be seized as pretence to rescind the WTO case before the antagonisms of hearings, judgment, appeal and retaliation unfold.