Germany is a non-nuclear-weapon state. Our bombs are there yes, but if you use one of our bombs without our approval there will be hell to pay. An invasion of Greenland will be all but guaranteed. Whether Germany will retain its military the next day is questionable.
I see you don't want to understand my point.
Why exactly do you think Germany is a non-nuclear weapon state?
It is ok for Germany to detonate nukes on someone who attacked NATO. The approval of the aggressor is not necessary.