U.S. President Donald Trump is threatening more tariffs. Starting on September 1, the U.S. plans to put an additional 10 percent tariff on Chinese goods worth 300 billion U.S. dollars. This came just as the two sides agreed on another round of talks in September. China has slammed the announcement, and vowed to take necessary countermeasures. Is Trump desperate or is he just trying to gain leverage in the next round? Li Yong, a senior fellow at the China Association of International Trade, said that this is a childish decision because both sides have passed four rounds of trade talks.