The commander of the base wrote, "I do not presume to understand current politics, but what I do know is the concerns of the US administration discussed by Vice-President Vance on Friday are not reflective of Pituffik Space Base." in an email and was thus dismissed. In dismissing her, the Pentagon stated this reason. "Actions [that] undermine the chain of command or to subvert President [Donald] Trump's agenda will not be tolerated at the Department of Defense."
Not that the rule of law matters, but the VP is not in the military chain of command. There is no vice commander-in-chief. It goes pres then his Chiefs of Staff/Generals.
Of course they could just lean on the undermining trumps agenda of stripping Greenland of its resources, but that's not why the base was there. Or I guess that is why it's there now.....idk.