Trump’s Copper Tariff Surprise Puts Spotlight on Huge US Stockpiles

Donald Trump kicked off a massive movement of copper into American ports by telegraphing tariffs in February. Now the US president may have initiated the reversal of what’s been a hugely profitable trade.

His administration shocked the metals world Wednesday with a tariff proclamation that spared refined copper — the biggest category of the metal — from a 50% levy. US copper futures, which had surged in recent months on the prospect of tariffs, plunged the most since the current form of the contract started trading in 1988.