Denmark is interesting here. Sweden and Finlad are moving from neutrality into officially being in the NATO camp so that explains them, The baltics are tiny, right on the Russian border and have been screaming about the threat Russia poses for a decade, so no surprises there that they want to tighten up security relations with the US.
But Denmark is odd, they’ve been in NATO forever and arent exactly on the front line even in a Gotland scenario, so whats going on there?