Like the “shot heard round the world,” the American protectionist move has politicians and economists in industrialized nations strategizing with their spreadsheets. From Porsches to prosciutto, every country is scouring trade numbers to see what can be tit for tat in the event of all-out global trench digging. Canadian industries, on the other side of the bridge from where the shot was fired, have their helmets on. The volley is a prod to put all things we peddle—and to whom we peddle to—into perspective. Steel, for instance, has much in common with oil, natural gas and petroleum products businesses. Both are products sourced from a plentiful domestic endowment of resources — iron ore and hydrocarbons. Both fight for market share in a fiercely competitive global market. Both have long been vulnerable to the vagaries of government policy. Both are hugely important to their provincial economies, Ontario and Alberta respectively. […]