The U.S. economy has struggled with high unemployment for the past 5 years. As a result, there was a backlash against buying foreign products since they resulted in American factories going out of business.
American companies are responding by increasing their level of American-made products in the stores. For example, Walmart is aiming for 35% of its products being American made by the end of next year. This investment in the American economy makes the U.S. dollar stronger against other currencies, especially those in developing countries.