At best -- at best -- the rhetoric about Canada and Greenland is just yet another distraction from all the other domestic crap he and Musk are pulling. At slightly less than best, he wants to scare other countries into making concessions favorable to the US (or at even less than best, favorable to Trump and his cronies).
But yes, I would not be terribly surprised if Trump were to use boots on the ground -- or at least the threat of such -- to expand the US's territory in some way.
Underestimating your enemy, or buying into all these media talking points about his will-they-won't-they energy and "epic trolling", will have disastrous effects. The most culpable person down the list after the apathetic are those who refuse to take tragedy and security threats seriously.
But yes, I would not be terribly surprised if Trump were to use boots on the ground -- or at least the threat of such -- to expand the US's territory in some way.