US Copper Stockpiles Reach 21-Year High Ahead of 50% Tariff

US copper inventories have risen to their highest level in 21 years as traders and manufacturers race to secure material before a 50% import tariff is imposed on 1 Aug 2025. Industry participants say the government has yet to release key implementation guidelines for the levy, leaving buyers uncertain about customs procedures and potential exemptions only two days before the measure takes effect.