
I think it’s more likely to be about the USA’s strategic control of the Arctic as the ice melts and ships can operate more easily. Right now it’s bordered by Russia, Scandinavia, Greenland, Canada and a little bit of the USA. Trump wants all of the Canadian and Greenland coastline to be the USA’s, so Russia and the USA can effectively control the Arctic Ocean and its shipping routes, and threaten Europe from the north. This is something that’s so simple even Trump would think of it when looking at a globe.
Other factors include resources, including fresh water, and Trump’s ego and inability to relate to others except through more or less lame attempts at dominance and bullying. Also that Trudeau out-handshook him a couple of times.
Vote, everyone!