Trade WarDonald Trump hasn’t even been sworn into office and is already roiling currency markets. The yuan, Mexican peso and Canadian dollar all slid this week on Trump’s social media claim that he will add tariffs on these three countries unless they stem the flow of drugs and illegal aliens into the U.S. The yuan fell against the dollar to its lowest level in four months. While Ottawa and Mexico City threatened retaliation, Beijing reacted more calmly by stating that neither country would win a trade war. China’s Embassy spokesman in Washington Liu Pengyu said, "About the issue of US tariffs on China, China believes that China-US economic and trade cooperation is mutually beneficial in nature." The Chinese Communist Party’s flagship...