The Trump administration has ignored the core principle of the World Trade Organization (WTO) rules – the most-favored-nation treatment, and imposed a 10% tariff on Chinese exports to the United States in accordance with the International Emergency Economic Powers Act, a domestic law of the United States. This behavior is a typical unilateralism, which seriously tramples on the international order based on international law and undermines multilateralism and international rule of law. Multilateralism has been the basic and dominant institutional arrangement and value concept of the international community since World War II, and has promoted world peace, stability, development and prosperity.