The Mexican government plans to update the products it has applied duties to in retaliation for the U.S. government’s section 232 tariffs on steel and aluminum. So far the duties have had a political rather than economic impact. Controversy over the tariffs may hold up the passage of the U.S.-Mexico-Canada Agreement. Yet, Mexican exports of steel and aluminum to the U.S. increased 5.5% year over year in the second half of 2018 after duties were applied in June, led by a 148.0% rise in shipments by ArcelorMittal and 11.7% by Ternium. At the same time imports of products targeted for retal...