I think they can get more military presence, if they talked normally, with respect, said "thank you" to Greenland and to Denmark etc. There is no "security reason to usurp Greenland as such.
But we know that Greenland's ice is melting and there is plenty of natural resources under it. This US administrative seems hungry for natural resources.
Attacking judges, attacking media, attacking political opposition (constantly, they mention Biden in every interview almost), attacking allies... it seems they want some chaos and war, possibly even against Europe. The question is why, what is the real plan behind all this.