From Protectionism to Free Trade ——Discussing the Historic Change of the Foreign Trade Policy of U. S. during 1930s and 1940s

During 1930s and 1940s, historic change taking place in the foreign trade policy of U.S. was from protectionism to free trade. U.S. had pursued a protective policy from the day of its independence to 1933. After fierce struggle between the trade liberalists and the protectionists, very important change happened in negotiability of tariff, level of tariff, unconditional most\|favored\|nation treatment, allotment of the right of making trade policy between the president and the Congress, and the signing of multilateral trade agreement. The change had the nature of free trade. The reasons of the change were the negative result of protective policy, the change of international economic structure including the strengthening of competitive power of industry of U.S., and the trade liberalists' long\|time struggle for free trade.