A 50% tariff is inflationary so won't help. America has no copper resource. Bingham Canyon is almost depleted. The US consumes 1.8 million tonnes of copper p.a.. Its top 4 producers can ONLY supply 694,000t=38% of demand: Morceni 286,000t, Bingham Canyon 202,000t, Safford 120,000t, Sierrita 86,000t.