https://en.wikipedia.org/wiki/1968_Thule_Air_Base_B-52_crash
(Accidental crash causing the (non-nuclear) explosion of 3 hydrogen bombs and the loss of a 4th.)
https://en.wikipedia.org/wiki/Project_Iceworm
(A network of mobile nuclear missile launch sites under the Greenland ice sheet.)
However after the cold war US activity there has been cut to a single base with just over 100 men.
So with the re-newed interest and a willigness to seriously mess up the NATO alliance - what does the US want in Greenland this time around?
Minerals, data centers, launch rockets into space, prepare for climate change, maybe something with the northern sea route?
It is very unclear.