If you look into the auto industry, Ford and GM will,each be looking at a billion dollar a year materials price increase. How do you think that increase passes along? I will tell you that the tire industry buys zero US steel, because no one in the US makes the product. That is a 100 million dollar material increase and the product still comes from out the country. It would be great to have US sourced product, but the US typically is from recycled ore and is not of the quality of mined ore.
The thing is that steel is not on a tariff if it is in a manufactured product so vehicles, and tires and other products coming into the country with steel in them now have built in materials cost advantage over US product. Multinational companies have an incentive to produce outside the US and ship in to save tariff cost. There were tariffs set for truck tires from China last year but Trump had them killed. So for Chinese tires, they get no tariff at all even while selling product below material cost because they have Chinese government assistance and now on top, the US made products have to pay 20% more in materials cost than the Chinese. Lose - lose for US production
As soon as the proposal of tariffs were announced, suppliers immedidialy started to raise the prices of materials. Aluminum companies have already raised there prices 10% even before the announcement to match the tariff priced product.
All and all, the cost of a ton of products go up immediately and that is passed on to the consumer. Mean time, the tariff is a nice little tax for the government to have.
All of this and on time, the other countries are pissed you are putting stress on their products and start a trade war. US products get tariffs going into their countries and other industries suffer.