The Globe and Mail reports in its Saturday edition that Canadians will soon find out what can be salvaged of North American free trade. The Globe's Tim Shufelt writes that the renegotiation process for the U.S.-Mexico-Canada Agreement, or USMCA, is already effectively under way, which could reshape Canada's economic fortunes for years to come. We know what a good outcome looks like: The USMCA survives largely intact, with Canada forced to make key concessions while retaining preferential access to the U.S. market with minimal tariffs. What if it all falls apart? Many economists believe the odds of such a rupture are low, but it is not hard to imagine the process going off the rails. Over the past few weeks, U.S. President Donald Trump has gone on the attack once again, threatening Canada with devastating tariffs, calling Prime Minister Mark Carney "governor" and toying with the idea of scrapping the "irrelevant" trade deal altogether. Within a year of the collapse of USMCA, Canadian gross domestic product would drop below baseline by about 1.8 per cent, according to a recent Oxford Economics report. The Toronto Stock Exchange would likely dip by about 4 per cent, the report said. Not good -- but not catastrophic either.