While some Americans say they are willing to pay more for the benefits of protectionism—more jobs sewing clothes and assembling machinery and electronics—their enthusiasm may wane when the negatives on the export side of the ledger kick in. First to be hit would be American farmers and ranchers, who often export a third of their harvest and herds. Then it cascades down. Smaller crops mean fewer tractors, which mean less steel and so on. Then the folks who make big-ticket export items like jets and bulldozers are targeted for retaliation.