Ummmmm.....we have contingency plans to invade Mars at the DoD.
And FEMA has contingency plans for a literal zombie apocalypse, and the CDC war games various pandemic scenarios.
Of course, the FEMA zombie apocalypse literature tells people to obey the government and head to government shelters and only has slow movers. I guess slow movers are more in line with the other government workers FEMA deals with but yeah, that plan shows a whole lot of nothing. If there were a real zombie event, it would most likely be rabies-based and they'd be fast for a while. But the government wants us to move to their shelters. I'm not feeling a lot of trust in authority here.
so what does that say about wargaming the invasion of Greenland? First, there's one major port, one major "city" [large town?], no significant military presence, and the only realistic reason for the invasion is to headstone incursions by other powers. With Thule military base, I doubt the actual Danish/Greenlandish population would notice an "invasion" beyond the absence of Russian or Chinese overlords suddenly descending upon them.