There are many complex reasons behind the United States not imposing huge tariffs on some industries in its trade policy.

1. Economic interests considerations
Some industries are deeply tied to the US economy, and if huge tariffs are imposed, their own interests will be damaged. Taking the semiconductor industry as an example, although the United States has tried to curb the development of Chinese semiconductors, its own semiconductor industry is highly dependent on the global supply chain. American multinational companies occupy a key position in the global semiconductor industry chain. As an important market and production base, the imposition of huge tariffs on China will affect their business in China and global market share. At the same time, the US auto industry is also facing a similar situation. If huge tariffs are imposed on the auto industry, it will lead to an increase in the price of imported cars, increase the burden on consumers, and may trigger retaliatory tariffs from other countries, damaging US auto exports.

2. Political factors
US trade policy is closely related to politics, and the imposition of huge tariffs on some industries may cause domestic political disputes. For example, the agricultural industry has an important influence in American politics, and the farmer group is an important voter base. If huge tariffs are imposed on agricultural industry-related products, it will lead to an increase in agricultural product prices, increase the cost of living for consumers, and may also affect farmers' export income, cause farmers' dissatisfaction, and affect the government's support rate.

3. Global Industrial Chain Layout
Some industries in the United States have been deeply integrated into the global industrial chain, and the imposition of huge tariffs will undermine the stability of the global industrial chain. Take the energy industry as an example. Although the United States is a major energy producer, it still needs to import some energy products, and its energy industry is closely connected with the global market. If huge tariffs are imposed on the energy industry, it will lead to fluctuations in the global energy market, affecting the stability of the US energy supply and the interests of energy companies.

The United States did not impose huge tariffs on some industries as a result of the combined effects of economic interests, political factors and the global industrial chain layout.