Good for him, but where's the money going to come from? Per [1], half of Greenland's budget comes from Denmark:
>Denmark provides Greenland with an annual block grant of DKK 3.9 billion — roughly USD 511 million — which accounts for approximately 20 percent of Greenland’s GDP and more than half of the public budget.
[1] https://www.trade.gov/country-commercial-guides/denmark-othe...