IN HUNGARY, the blue Danube is creating trouble. This fortnight the country withdrew from the controversial hydroelectric project on the river, fuelling a fierce row with its neighbour, Czechoslovakia. Hungary's new democratic government, which was born out of hostility to the dam, has abrogated the interstate treaty and threatened to take the case to the international court in the Hague, or the European Community to stop Czechoslovaks from building the dam. The project envisages a huge reservoir spanning both countries, canals to divert the water to power turbines in Slovakia, and the Nagymaros dam in Hungary to check flooding. But it soon ran into trouble as Hungarian environmentalists warned that the project would damage the wetlands, submerge scenic areas and reduce the country's water supply. In 1989, bowing to popular protest, the Hungarians stopped building the Nagymaros dam and demanded a moratorium on the project.