It takes 2 to make a trade, and the best strategy for an iterated prisoner's dilemma scenario is tit-for-tat. The party that started the silliness should end it, but until then, Canada should rightly consider stronger ties with the Europe - they do share a border with a European country after all.
Depending how you count "borders" and "European countries" they share a border with 2 (France via St Pierre and Miquelon, Denmark via Greenland) and share a landlord with a third.
The best strategy is tit-for-tat with eventual forgiveness attempts. It's way too soon for that (the US is still controlled by Republicans) but one eventually re-opening trade might be optimal, assuming there's still a USA to trade with.
Tit-for-tat inherently forgives the moment the other party stops defecting, in a game theoretic sense. It's "start friendly, every future move copies other party's previous move".
