In the U.S., there have been winners and losers under NAFTA, much as there have been in Mexico and Canada. That is the nature of trade. Perhaps the biggest winners in all three countries have been consumers.During his presidential campaign, candidate Donald Trump often characterized the 23-year-old North American Free Trade Agreement (NAFTA) with Canada and Mexico as a disaster for the U.S. He declared that he would withdraw the U.S. from the trade pact if elected, claiming that it cost the country jobs and caused a huge balance of trade deficits with both Mexico and Canada. Mr. Trump’s opinions about NAFTA were consistent with his “America First” views, distrust of international trade agreements and populist fears of globalization. After b...