The World Trade Organization (WTO) recently ruled on the case brought by the US, Canada and Argentina against the moratorium imposed by the European Union (EU) on imports of genetically-modified (GM) food and crops. Although the WTO's ruling has been greeted by the complainant countries as a victory, it found in their favor on only one narrow technical procedural issue, and it rejected more substantive challenges to the EU moratorium. In this article, we analyze the WTO report and explain the issues at stake, focusing particularly on the question of why the USA chose the WTO as the forum for its challenge to the EU moratorium, and whether it was wise to do so. Has the USA achieved its aims through the trade-specific WTO, or should it have taken its challenge to the more hostile, but environment-specific forum of the Cartagena Protocol on Biosafety? Alternatively, should the USA have refrained from mounting an official international challenge at all?