On the one hand, it comes across as galling American arrogance and stupidity to act offended that Canada has sought out other trade partners when the US under Trump has been arbitrarily ripping up our trade deals, threatening us with economic warfare and annexation and repeatedly telling us that they don't need anything manufactured or produced in Canada.
On the other hand, Trump is eventually either going to annex Greenland by force, or lose interest in it because it's too much work. And at that point, he'll probably turn his attention back to his dream of annexing Canada, and this is the exact kind of pretext he and his minions will be using.