The Trump Administration is reportedly considering imposing duties on a range of products, with a early focus on steel imports. The administration opened an investigation into steel imports, and Wall Street believes that steel tariffs are coming, with the government claiming that they pose a risk to national security. 

Top steel exporters to the US are Canada, Mexico, Brazil, EU and Japan. China ranked 11th among US steel imports after the Obama administration slapped a 500% tariff on Chinese steel, on charges of dumping steel below costs. China had then reportedly diverted steel via Vietnam - imports from Vietnam surged 300% between 2015 and 2016, compelling the Obama administration to open an investigation (the results of which are yet to be released). 

If the US announces steel tariffs, retailatory measures from other countries are likely. The auto industry in the US which relies on steel imports have opposed the move, while domestic US steel producers are pushing hard for the tariffs, saying that cheap imports have forced them to close factories and layoff workers.