Global National May 31 2018 6:34pm 01:12 Why is President Trump instigating a global trade war? There’s no clear motive for Donald Trump’s stiff tariffs on close American allies. Jackson Proskow reports on what Trump may be trying to accomplish. Scott Thompson: Like Calgary weather, if you don’t like ‘The Donald,’ wait a minute Canada hits back against U.S. with more tariffs: but what are they and how do they work? ANALYSIS: There’s no clear strategy behind Trump’s tariffs Responsive site?