Trump is absolutely sure that the Chinese are not "playing fair" with trade. They require American and European companies to take on Chinese partners in order to do business in China. Also the Chinese government does not protect foreign IP. Starting a trade war is bad, but allowing unfair practices to continue is worse. And I guess the record low unemployment, along with the U.S. having a strong economy while the rest of the world drifts towards recessions, is your proof that the tax cut didn't work.