Pentagon told Pope's top diplomat to 'take its side' on US military ambitions: report

Denmark, even with NATO help could probably not stop the US from capturing Greenland. But then what? The US military is not at all suited to be an occupying force. It is really bad at that (to be fair, with modern communications and technology it is really hard to effectively be an occupying force against local resistance). So they would have destroyed most/all of their military alliances and gotten control of an island that they have to continue to keep fighting to hold, all for the ability to have a military base on Greenland like the one they have now hassle free.

it will be a lot easier now that the US has used up its 3 year stockpile of smart weapons in 30 days in an unwinnable war.

of course Denmark would lose a war with the US. but the question is, how would American public opinion wear dead and wounded American soldiers from a war of conquest in Greenland? Trump is operating under the assumption that there would be no fighting. that might well not be the case.

Denmark HAD help, and a whole lot of it. It came out fairly recently that a rather large coalition of European states were prepared to go all-in and take a military confrontation with the US over Greenland if that's what it came to. The US may have forgotten the meaning of the words "friend" and "ally". Europe has not. We're talking countries preparing battalion-level ground formations, which for a place like Greenland is insane (a battalion basically increasing the current population of the island by something like 2%, *each*), as well as significant air and sea assets. Hell, France readied a carrier for deployment. The US could still have taken it, no question about that. But it would have been very, very expensive for them, in resources and in lives. And in global reach since, after all, you don't exactly get to keep the likes of Ramstein AFB if you've attacked and killed German troops defending an allied nation.

That's why several European nations sent tripwire forces to the Island in [Operation Arctic Endurance](https://en.wikipedia.org/wiki/Operation_Arctic_Endurance) under the cover of an army exercise. Sure even if all those nations committed, nothing they could over could prevent the US from taking the island, bar the French or British deploying nukes, but it successfully convinced the American leadership (for now) that this would be a costful and foolish endevour.