Recent developments suggest the US is stepping up efforts to strengthen supply chain security across zinc, critical minerals and copper, using a mix of domestic investment, cooperation with allies and trade policy tools.
In zinc and critical minerals, the US approach appears to be moving along two parallel tracks: rebuilding domestic processing capacity while also anchoring supply from allied countries. Korea Zinc recently disclosed plans to develop a large-scale integrated non-ferrous smelter in the US, following a conditional commitment involving the US Department of Defense and the Department of Commerce. The project is planned for Clarksville, Tennessee, the site of Nyrstar’s existing zinc smelter. Korea Zinc has reached an agreement with Nyrstar to acquire the smelter site, providing the physical location for the planned redevelopment, while the transaction remains subject to customary conditions and regulatory approvals. The new facility is expected to cover zinc, lead and copper production, alongside a range of strategic metals such as antimony, germanium, gallium and indium, with phased construction and commercial operations targeted for around 2029, after which the old Clarksville Smelter's outdated capacity would expect to be phased out.
Commenting on the project, US Secretary of Commerce Howard Lutnick said the Tennessee smelter would “enable the US to produce 13 critical and strategic minerals at scale”, supporting sectors including aerospace and defence, semiconductors, AI, quantum computing, automotive and industrial applications. He added that the project would strengthen US national and economic security by reducing reliance on foreign supply, while also giving the US preferred access to part of Korea Zinc’s expanded production in South Korea. While the project remains subject to regulatory approvals and further clarity on the exact way of execution, market participants generally view it as part of a broader effort to rebuild US-based smelting capacity in zinc and other critical metals, where domestic processing capability has been limited for decades.
At the same time, the US is not relying solely on domestic capacity. Nyrstar’s antimony project at Port Pirie in South Australia has recently been included in the project pipeline under the US–Australia Critical Minerals and Rare Earths Framework. The Port Pirie project is expected to begin producing antimony metal from a pilot plant in 2026, with potential to scale up to around 5,000 tonnes per year by 2028, equivalent to roughly 15% of global supply. Although the project is located in Australia, its inclusion in the framework effectively links future antimony output to the US and its allied supply chain, rather than implying any physical relocation of production.
In copper, the policy approach looks different. Rather than direct investment in more smelting capacities, the US has increasingly been using tariff and trade measures to influence flows. With long-term demand growth expected from electrification, AI data centres and defence-related industries, changes in trade conditions have made the US market more attractive for overseas refined copper, encouraging part of the global deliverable supply to move into the US system.
Overall, recent moves across zinc, critical minerals and copper point to a broader shift in US metals policy. Instead of relying on a single solution, the US appears to be applying different tools depending on market structure. For metals where processing capacity is scarce and strategic considerations are more prominent, the US appears more inclined to promote capacity build-out through direct investment and policy support, while for metals with greater global liquidity, trade and tariff measures are increasingly being used to influence resource allocation. Whatever approach the US is taking, the actual impact on supply is set to depend on project execution, regulatory progress and market responses over time.
