US imposed a 25 percent tariff on virtually all goods produced by their two top trading partners — Canada and Mexico. At the same time it also imposed a 20% tariff on all China goods. As a result, the average tariff level is now higher than at any time since the 1940s. China and Canada immediately retaliated.China hit back with a 15 percent tariff on American agricultural products and the Canada putting a 25 percent tariff on $30 billion of US goods. Mexico vowed retaliatory tariffs.
Source: Vox