Of the 193 countries in the United Nations, exactly three haven’t adopted the widespread use of the metric system: Myanmar, Liberia, and the United States of America. Of those three, the US is the country that really stands out. It has the biggest economy in the world, does an incredible amount of international trade, and has immigrants from every country in the world If there was one country on paper that should be using the metric system, it is the United States. Learn more about your ad choices. Visit megaphone.fm/adchoices