The U.S. International Trade Commission on Friday struck down a 300-percent tariff against narrow-body Canadian jetliners, ruling against American-based Boeing and siding with Montreal-based Bombardier. The latter company made a $5 billion deal with Delta Air Lines, which Boeing claimed to be a violation of U.S. trade laws. Boeing attempted to argue that Bombardier is a direct competitor, thus justifying the 300-percent tariff. The panel, however, claimed that Bombardiers trade practices have not materially harmed Boeings business. The surprise ruing from the trade commission comes as a growing number of U.S. companies file complaints against overseas rivals, hoping to win favor with President Trumps America First trade outlook.