President-elect Trump has promised to impose steep new taxes on trade, including a 10-20 percent tariff on all imports, at least a 60 percent tariff on Chinese imports, and a 25-100 percent tariff on Mexican imports. At least a dozen estimates on Trump’s proposed tariffs show they will have a harmful effect on the American economy, supporting the standard view among economists that tariffs reduce trade and distort production, leading to lower standards of living…