https://www.youtube.com/watch?v=PaEPvrq5VFM

"Canadian Prepper" is at the fear porn end of the prepper spectrum but he usually has excellent logic. He allegedly has some internal government contacts and he is saying that the drones detect radiation signatures such as gamma rays. And that the US knows or has high probability assigned to nuclear weapons smuggled into the US waiting for detonation.

The disinformation, Iranian angle, China angle etc are disinformation intended to disrupt coherent discussion and commentary about the story.

The real story is allegedly 1) nuke detection 2) concealment to avoid mass public panic.

Makes sense, his idea is more focused than my flying lab theory, but that could be so too.