A really interesting analysis. There's a laundry list for selling, and the objection to not selling seems to boil down to "sentimental value".

I have no doubt the (capitalist) American looks at this in purely financial terms, while the (socialist) Dane feels that selling off their country folk seems a bit tacky.

A point not noted in the article is that selling Greenland isn't just selling land, it's selling people as well.