With a trio of executive orders, President Donald Trump has almost instantly thrown the world economy and his own goal of cutting inflation into turmoil. His tariffs against Canada and Mexico in order to stop illegal immigration and the illicit fentanyl trade led to retaliatory taxes by both countries on U.

Mr Trump’s announcement of the new duties ought to erase any doubts about his resolve to take a hard line on trade, heedless of warnings from businesses, diplomats and economists about the potential fallout.