"...it won't help his image if Mexico gets tossed aside."  Does Trudeau care?  Cash-for-access and electoral reform flip-flop didn't help his "beacon of light" image, either, on the home front. (Sure easy to feel pleased with him when he's in Washington and Berlin, though. Man!--a wonderful Minister of External Affairs...) 

 Trudeau can't win under the current scenario..." What a defeatist attitude.  Of course he can--Canada's better positioned than we were two weeks ago.  The celebrating you hear on Parliament Hill?  That's Justin's NAFTA negotiating team popping the corks just after the Trudeau/Trump meet.  Perfect performance in a perfectly-timed get-together. 

"...decisions will be made on limiting the losses..." You have Canada confused with Mexico.  Mexico has everything to lose.  All Mexico means for the USA, is drug enforcement problems, illegal alien problems, and, every single year, a drain on their humanitarian/industrial aid budget.