Trade retaliation looms from Canada, China, Mexico, and the European Union in response to U.S. tariffs. Four timelines lay out their responses, and the experience of American soybean farmers in 2018

The Trump administration on April 2 will give trading partner countries a proposed U.S. tariff rate based on their own rates, non-tariff trade barriers and other factors -- along with an opportunity to negotiate to avoid a "tariff wall,