The Globe and Mail reports in its Monday edition that President Donald Trump has undermined the credibility of both his word and the United States government's assurances by repudiating the commitments of previous presidents and Congresses, repudiating his own previous commitments and sometimes repudiating those repudiations. A Globe editorial says, as a result, it would be unwise for Canada to offer concessions on CUSMA, knowing any future deal could be undermined if Mr. Trump gets into a snit. No country has suffered more from tariffs and policy shifts than Canada. Canada endures tariffs on steel, aluminum and automobiles, and faces a fresh round of targeted tariffs -- some of which would violate CUSMA -- that will take effect on Aug. 19 unless a new agreement is reached. It is true that when Mr. Trump's term ends, the next U.S. president may try to reassure allies that the U.S. can once again be trusted as a responsible partner. But the world knows that America is always one election away from another MAGA White House. The Globe says no deal signed with the U.S. is a secure deal. World leaders once viewed an American president's word as reliable, but that is no longer the case, making the world more dangerous.