How important is international trade to the U.S. economy? In terms of volume of exports and imports, what country is the United States’ most important trading partner? Was the United States the world’s leading export country in 2012? If not, which country was? Place the following four countries in descending order in terms of exports as a percentage of GDP: the United States, Belgium, Canada, and Japan. What key factors account for the rapid growth of world trade since the Second World War?