(FORTUNE Magazine) – Just months ago, the experts were writing off exports. Yes, U.S. manufacturers had become competitive on price and quality, but recession-ridden Europe and Japan simply didn't have much reason to buy. The case seemed airtight after merchandise exports stagnated through the first three quarters of last year. The fourth quarter blew conventional wisdom out of the water. The volume of merchandise exports surged 30% at an annual rate, the biggest increase in 14 years. Sales to Japan remained sluggish. But buying rebounded briskly most everywhere else -- Western and Eastern Europe, the Near and the Far East, Canada and Latin America. Jim Haughey, research director at Cahners Economics, says U.S. companies are increasing global market share in computers, telecommunications equipment, even autos and trucks. If this keeps up, Americans will start exporting snowballs to Antarctica. Before sending a marketing team to the South Pole, however, consider the element of wisdom in the conventional wisdom. Japan and Western Europe, which buy one-third of U.S. exports, remain in a funk. That hurts high tech: Exports of what the Commerce Department calls advanced technology products rose only $1 billion in 1993, to $108 billion, after growing rapidly in previous years. Also consider that a fifth of the year-end gain came from aircraft shipments, which swing wildly from one quarter to the next. Since orders from foreign airlines have slumped in recent years, the long lags before shipment guarantee that aircraft exports will resume their downward trend. Machinery and equipment provided most of the strength in the fourth quarter. While fundamentally robust, shipments of these capital goods are volatile too, so it wouldn't be surprising if they cooled off in early 1994. The point still stands that the conventional wisdom was too pessimistic. Exports won't boom, but they're on good footing. Industrializing countries need U.S. capital goods. So do reindustrializing countries in Eastern Europe. Increasingly affluent poorer nations will buy more American consumer products. And U.S. manufacturers are highly cost competitive, even though the dollar has been rising for the past year and a half, often sharply, against all major currencies except the yen. Versus the pound, for example, the dollar has jumped 30%, yet the value of shipments to Britain increased 16% in 1993. Says Stephen Cooney, trade analyst at the National Association of Manufacturers: ''The fact that our exports to the U.K. outperformed their recovery says that U.S. industry is competitive.'' The key competitiveness ingredient has been strong productivity growth coupled with modest wage increases. From 1990 to 1992 (the last year available for international comparison), U.S. manufacturers' unit labor costs rose 1.7% a year on average. That was less than half as much as any major European country's, and minuscule compared with Japan's 13%, measured in dollars. With their unit costs down 2.2% in 1993, the Americans seem sure to have kept the lead, putting them in a strong position to capitalize on economic recovery elsewhere. Says Cooney: ''Once growth in Europe comes onstream, our exports to them will grow faster than their economies.''

CHART: NOT AVAILABLE CREDIT: FORTUNE CHART CAPTION: Merchandise exports