The Globe and Mail reports in its Tuesday, Feb. 14, edition that as Prime Minister Justin Trudeau prepares to renegotiate the North American free-trade agreement, he still cannot be certain how much of an economic bruising Canadians will face under President Donald Trump or a Republican Congress. An unbylined item in The Globe reports Mr. Trump said Monday the United States will only "tweak" trade ties with Canada. The Globe says Mr. Trump's America-first trade policy has the potential to embolden protectionism within Congress as well as empire building among U.S. government departments. The Globe notes few Canadians alive have experienced a serious trade conflict with Americans. Canada has relatively little leverage when confronting a hostile trade action. It has potential allies -- U.S. governors of border states and American chief executives who conduct significant business with Canada -- but only selective leverage over the United States, and few, if any, ace cards. Trade experts say, however, that if Canada is backed into a corner by U.S. measures to restrict or block shipments to that country, it must only threaten retaliation if it is prepared to deliver.