The US has invoked Article XXI of the GATT 1994 to justify its tariff measures on imports of steel and aluminum. However, the US’ tariff measures are not imposed for the protection of the US “essential security interests” but for economic and trade reasons. They do not satisfy the conditions listed under Article XXI (b) (i) to (iii) and should not be justified by them. They should not be considered as either national security measures or safeguard measures, but as ordinary trade restriction measures that are inconsistent with the WTO rules and the US obligations. A panel or the Appellate Body not only has the jurisdiction to review this dispute, but is also capable of making findings and providing a recommendation. Even if the US has the discretion to impose tariff measures under Article XXI (b), whether it has been acted in good faith, is still subject to the WTO review. As regards the tariff measures, the US has not acted in good faith.

Many are crying foul over the Trump Administration’s use of steel and aluminum tariffs, claiming that imports are not a threat to the US national security. Rather, it has been argued that the tariffs are a pretext to gain strategic advantage in unrelated trade negotiations. Members of the Trump administration have hailed subsequent trade concessions as proof that the tariffs have been successful, which, if proven, could raise a credible question as to whether the President exceeded the scope of his authority. Domestic and international challenges have already begun with the US courts being a more effective forum to the challenge the legality of the tariffs than the WTO.

With the continuous development of northeast Asian integration, the establishment of free trade zones between China, Japan and South Korea has become a development trend. This paper USES the GTAP model to simulate the changes and impacts brought by the reduction of agricultural tariffs in the free trade zones of China, Japan and South Korea on agricultural trade. The research results show that: first, the gradual reduction of tariff barriers for agricultural products of China, Japan and Korea will have a greater trade effect on China; Second, the creation effect of China-south Korea trade is far greater than that of China and Japan. Third, the reduction of agricultural tariffs will promote the growth of the overall economic aggregate of the three countries and change the terms of trade.