Well, sorta.
The US's main power projection strategy is still (and has been for decades) to have an aircraft carrier group parked about 1000km away from the coast of whichever nation they're attacking, pouding their target with airpower and cruise missiles whilst being far out enough that most cruise missiles can't even reach them and those which can take so long that the carrier group has plenty of time to prepare and defend itself.
The Chinese and the Russians both developed hypersonic missiles exactly to counter that, as such missiles get there much faster so the carrier group has maybe half a minute of advanced warning to try and take them down rather than 10+ minutes.
This strategy has been very successful against militarilly second and lower tier nations, which is why the US has been using it since the first Iraq war.
However, for all its underinvestment in its military, Europe isn't second tier (and neither is China).
As for the second part of your post, "boots on the ground" is exactly were the US massivelly sucks beyond the initial invasion stage: they're great at getting there and breaking shit up whilst completelly sucking at actually holding territory. Personally, from the videos I've seen of US troops trying to "create good will with the locals" in places like Afghanistan, they seem to be completelly shit at understanding and respecting the way of life of the locals and they reeking with a mindset of "I'm a member of a superior civilization trying to civilize the barbarians" (which, as an European, I find hilarious, since America isn't actually all that culturally or societally civilized - especially in treating people as actual human beings - compared just about all European countries).
All this to say that the US invading Greenland would succeed, but directly cost the US far more than even Afghanistan and in a far shorter time, and they would almost certainly lose control of it in at most a decade or two, not least because they totally suck at getting the locals around to support them: trying to take on the most hardcore and resilient of the descendants of the Vikings in a land which in some ways is the polar equivalent of Afghanistan - huge, harsh and with massive uninhabited and hard to occupy areas - whilst the people there don't at all feel they have an inferior culture to America's (so they're hardly attracted by the prospect of becoming American citizen) seems to me like an impossible task.