You do realize Denmark/Greenland is (well, at least used to be before this circus act) your ally?
If there were a path back, there’d be a point. But in this discussion, everything has already happened. There’s not much point in saying “if you hadn’t”. Well, Trump did. Having done what he did, nothing to do now but to go full bore.
Now that we are on a war footing, potentially with our erstwhile allies who have no interest in renewing the alliance given present conditions, the only path to preserve US control is aggression.
Think of it like this: America fucked up, and maybe with other allies at other times we could have gone back to the old ways. But these aren't those allies and this isn't those times. So we close doors on old friendships and go at it the other way.