https://reason.com/2020/01/30/trumps-tariffs-keep-hurting-american-manufacturers/
Interestingly, the president does seem to understand that his original tariffs on steel and aluminum have had a negative impact, as predicted by many economists.
The recent proclamation acknowledges that the metal levies have reduced imports of foreign metals and that, as a result, U.S. imports of some products made with those metals "have significantly increased since the imposition of the tariffs and quotas." The net effect, the proclamation continues, "has been to erode the customer base for U.S. producers of aluminum and steel." Exactly!
This outcome is a well-documented impact of tariffs on intermediate goods such as steel and aluminum. First, these tariffs raise the cost of the imported metals, and as a result, that raises the production costs for American manufacturers that use these inputs. Unsurprisingly, this means higher prices for American-made products and an increase in imports of goods made with those metals.