President Donald Trump announced on Wednesday night that the United States will impose a 50 percent tariff on copper, effective August 1. Trump wrote on Truth Social that he came to the decision after a "robust NATIONAL SECURITY ASSESSMENT."

President Donald Trump mentioned Tuesday — almost in passing — that he planned to impose a 50% tariff on copper imports. It still hit like a bombshell, with potential to shake up U.S. efforts to expand,

Prices for the metal hit a record high after the president suggested a higher rate than many analysts were expecting.