I believe that's true: if Trump attacked Greenland, NATO would fall apart (regardless of Europe's response, if they allow it or not), and then Putin would have

I believe that's true: if Trump attacked Greenland, NATO would fall apart (regardless of Europe's response, if they allow it or not), and then Putin would have a once in a generation chance to take the baltics, maybe mess with Poland. He would have to take that chance, and then Europe would have to retaliate, and its effectively WW3. Spooky times, let's hope things fizzle out back to a rule based Pax Americana. Edit: Interestingly, the likelyhood of things fizzling out would jump up quite a bit if Trump or Putin were to die. I think the US system of government is prone to electing Trumps, but it's not a given, I think the cult of personality would die and things would relax for now.