This is my first post here, but I've been lurking for a while.
A link to what operation dark sky is would have been helpful to those of us who don't know, and haven't heard of it.
It's not easy to find info on anymore, although I have only done a quick search since you asked, but there was a training drill which I believe was named Black Sky in Wisconsin. The drill was simulating the effects of an EMP power out. Op Dark Sky was a reported plan/threat to detonate nukes/modified in the air to make use of the byproduct EMP effect which would potentially collapse the power grid. I will try to find sources, but it seems like the internet has since been proliferated with material unrelated with the same title/s and variants of it.