And with that we would likely start a major war. If things get bad enough due to climate change I'm sure things like could happen, though, or we'll see developed Western countries invading other Western developed countries again in order to secure resources. But we would have to be at or near the point of near complete international sociopolitical structure collapse.
It's a big master plan, first they bought Alaska, now they want to buy Greenland, then they will try and buy the north pole from Santa and BOOM: Canada is now a small country located inside the USA and must be absorbed xD
That actually already happened. After Denmark got occupied in WWII, both the occupied puppet government and the Free Danish Government claimed sovriegnty over Greenland. Greenland decided to not accept the legitimacy of either, and signed a separate (And technically illegal) Joint Protectorate agreement with the United States so they could stay neutral (They didn't want German uboats or the royal navy sinking their fishing fleet). Ironically, Greenland wound up having to honor the agreement, not the United States, as they entered the war after Pearl Harbor to "Protect" the US as per the terms of their agreement.
The Danish Ambassador to the United States was the person that assumed the nominal head of state role for Greenland, and was charged with treason by the Free Danish and Occupied Danish Governments for doing so. After the war, he returned to Denmark to face trial, but the charges were dropped. The US then offered to buy Greenland for $100 million, but Denmark refused and Greenland rejoined Denmark. It became fully a part of Denmark in 1953, and was granted self rule in 1979 (While still being part of the Kingdom of Denmark).