His father got along in private with Richard Nixon quite well and I suspect Justin will be polite with Donald Trump in private, although he may make public statement to feed raw meat to the Left in Canada and other nations.
Listen to this audio tape from May 1973 during the Watergate scandal
https://www.youtube.com/watch?v=DJKmTYlfgMI
I’ll give Justin Trudeau this in that he was smart enough to realize that Trump could win and that he might have to be dealing with him and thus didn’t comment too much on the US election while it was ongoing. Dissing Trump wouldn’t have been a smart move and he was quick to congratulate him and invite him for a visit.