What is Japan's main economic source?

Due to the limited domestic market, Japan is an export-dependent country with a small territory and poor resources. However, after the war, Japan pursued the line of "attaching importance to economy but neglecting armaments" and focused on economic development, which made Japan the second largest economic power in the world at the end of 1960s, and its economic strength was second only to that of the United States. Japan is poor in mineral resources, except coal and zinc, most of which depend on imports. The extent to which the main resources depend on imports is: coal 95.2%, oil 99.7%, natural gas 96.4%, iron ore 100%, copper 99.8%, bauxite 100%, lead ore 94.9%, nickel ore 100%, and phosphate rock. The forest area is 25.26 million hectares, accounting for 66.6% of the total land area, but 55. 1% of the wood is imported, which is the country that imports the most wood in the world. There are abundant hydropower resources, and the hydropower generation accounts for about 12% of the total power generation. Offshore fishery resources are abundant. Industry is highly developed and is the main pillar of the national economy. Gross industrial output accounts for about 40% of GDP, mainly concentrated in the Pacific coast. Keibon, Hanshin, Zhongjing and Kitakyushu are four traditional industrial zones, and then there are new industrial zones such as North Kanto, Chiba, Seto Inland Sea and Suruga Bay. Japan has established the development policy of establishing a country through trade since the 1950s. After China's entry into WTO, Japan began to gain the same equal status as other contracting parties. According to the basic principle of most-favored-nation treatment in GATT, free trade with most countries and regions has created favorable international market conditions for the continuous expansion of Japan's foreign trade scale. Since then, Japan's foreign trade has grown rapidly, mainly to the United States, Asian countries and European Union countries.