U.S. Trade Representative Robert Lighthizer has indicated a deal could be agreed shortly to cut section 232 metals duties on exports from Mexico and Canada. The agreement would likely take the form of quotas rather than tariffs. In turn that could unlock the potential for ratification of the U.S.-Mexico-Canada Agreement (USMCA), particularly if it was adapted to include the quotas. The tariffs have proven to be little deterrent to Mexican steel and aluminum exporters. There was a 16.0% year over year increase in Mexican exports to the U.S. in 4Q 2018 and by 10.1% in January. Tenaris a...