EUROPE IS moving rapidly toward federal union, in an atmosphere that ought to make Americans more than slightly uneasy. The current acceleration is proceeding at the expense of Europe's responsibilities abroad. That is clearly visible in the fading hope for the world trade negotiations, which are jeopardized by the Europeans' peculiarly disruptive and costly methods for protecting their farmers from foreign competition.

Trade, along with its steady expansion across national boundaries, has been a consistent force for economic growth ever since World War II. The current round of negotiations is an attempt to strengthen the rules of trade, make them fairer and extend them to areas -- like agriculture -- that they have not traditionally covered. The odds against success in these talks are rising. Of the three great centers of economic power, Japan remains basically protectionist. If Europe now continues to turn inward, that would leave only the United States and some of the smaller countries committed to open markets -- and plenty of American industries are hard at work to block any progress here. The deadline for this round of trade talks is the end of the year, and if they collapse, every trading nation in the world will suffer for it.

The European Community took a dramatic step toward union a week ago when, jumping ahead of its own schedule, it agreed to create a central bank by 1994. That foresees the creation of a single European currency before the end of the century, a tremendous transfer of sovereignty from the 12 member countries to a community that would then become, in all economic and financial matters, a true federal government.

In contrast, the 12 have been deeply divided among themselves over trade and farm policy. Until this week they were paralyzed, unable even to come up with an agreed position to bring to the world negotiations. Now they finally have a position, but one that's clearly inadequate. It would promise a microscopic reduction in farm subsidies. But it apparently proposes to do nothing about the most damaging of the community's trade practices, the dumping of its unwanted surpluses on world markets. Europe's leaders make it clear that they have grander things on their minds and haven't time for the tedious and narrow details of farm politics.

Rich and confident, the European Community is rushing toward unity at a remarkable rate while its impoverished eastern neighbors clamor to join. But the Europe of the 12 did not become rich by ignoring its trading interests abroad, nor is it likely to keep growing richer by ignoring them now.