I’m looking at the replies on this thread and wonder how many people have looked at Greenland on a globe? It’s strategically located in the North Atlantic, is near very vital sea lanes to the Arctic and both China and Russia want to develop the Arctic area. I know men from World War II who were stationed there. I agree that Greenland is living off Denmark (this was a subplot on the series Borgen with Sidse Babette Knudsen), but it is a serious offer as they have no defense.
My dad, when he was in the AF, had a TDY at Thule AFB.
And, to add to your point, Greenland makes Denmark an Arctic Ocean nation along with US [by reason of Alaska], Canada, Norway and Russia). If these five countries were to agree, we could divide up the economic rights of that ocean. (There would still be freedom of the seas for navigation.)