I don't have a very thorough understanding of the international money markets.

If Europe "dumps the dollar" - what does that mean in practice?

This article suggests that Europe could also call in US debt. Presumably the US could grandstand and not pay it. What are the consequences of that?

What everyone is missing is the tactical situation. How does this invasion work when Greenland had less than 100 miles of paved roads? If anything, this would be an occupation of their very few (just nine or ten) mining locations. And those don't move, so you cannot hide them from aerial bombings.

Even if the invasion never happens who is going to trust the United States anyway?

This is one scenario. But, there is another. More right wing elements of Europe (Poland, Hungary, Bulgaria, Italy) will refuse to join the boycott and we will have both a loss of NATO unity and a loss of EU unity. Chaos!

It will make the USA look like a dictatorship and evil, and NATO nations will boycott the USA and USA products.

The left confuse "Random shit demented Trump comes up with" with "Things that will happen".

Please, people, let's deal with the latter. That's crazy enough.