Farmers in the U.S. agricultural heartland that helped elect Donald Trump are now pushing his administration to avoid a trade dispute with Mexico, fearing retaliatory tariffs that could hit over $3 billion in U.S. exports. http://www.stltoday.com/business/local/please-no-trade-war-with-mexico-midwest-farmers-plead/article_340e1866-a368-5c24-b740-e71f9ea974e0.html