President Trump signed a proclamation on April 2, 2026, that tightens the Section 232 tariffs on imported steel, aluminum and copper, and rewrites the way those duties are calculated. Under the hood, the change is a valuation fix: tariffs will now apply to the full customs value of a covered product, rather than an artificially low foreign price.
The detail that matters is the tiered structure. Products built wholly or nearly wholly from aluminum, steel or copper, such as steel coils and aluminum sheet, will face a flat 50% on their full value. Derivative articles substantially made of the metals will pay 25%. Certain metal-intensive industrial and electrical grid equipment will be charged 15% through 2027, and products made abroad but assembled fully from American steel, aluminum and copper will face a reduced 10%. Items whose metal content is 15% or less are no longer covered.
The technical reality is that this builds on a ladder of earlier moves. Trump first invoked Section 232 on steel and aluminum in his first term, raised those rates to 50% in June 2025, and added copper at the same 50% rate in July 2025. The April proclamation extends the program to derivatives and closes the valuation gap that let imports dodge the full duty.
The White House casts the tariffs as the engine of a domestic buildout. In 2025 the United States rose to become the world’s third largest steel producer, and more than 4 million tons of fresh crude steelmaking capacity is set to come online within two years, in states that include West Virginia, Arkansas and South Carolina. Century Aluminum and Emirates Global Aluminum are teaming up on what the White House calls the first new American aluminum smelter in decades, planned for Oklahoma.
Copper is following the same path, with Ivanhoe Electric, Rio Tinto, Highland Copper and Wieland expanding mining, smelting and fabrication. As ever, the question is whether supply chains reshuffle fast enough to match the tariffs’ ambitions, but the direction of travel is now written into the code.
Sources
- Fact Sheet: President Donald J. Trump Strengthens Tariffs on Steel, Aluminum, and Copper Imports – The White House
- U.S. Expands and Increases Section 232 Tariffs on Aluminum, Steel, and Copper Effective April 6, 2026
