The article pictured above mentions an asteroid large enough to mimic a nuclear airburst, noticed only a day before a close flyby of Earth.
Right now, in the US and UK at least (likely elsewhere, but I’m not politically knowledgeable enough to point fingers in those directions) it’s fashionable to holler “fake news!” if a fact doesn’t agree with one’s assumptions and/or want-to-believes. Mostly on the political right, though I’ve sadly seen some on the left and even center catching the feelings-over-facts bug.
So. Imagine a rock from space smearing a city in a tense nation. The astronomy community says “hey, look, here’s video proof we saw it a day ago.”
And a few influential hawks shout back, sneering: “fake news! Fake video!”
Millions cheer for war. Saner heads are ignored — after all, didn’t Breitbart and Infowars and Trump (or the parallel orgs & people in another nation) say it wasn’t an asteroid? In fact it was a nuclear attack! And the [whoever is in the doghouse with the struck nation] did it! LET’S GET THEM!
This is one of the more out-there scenarios — more than likely, the “fake news” conspiracy theorist howl will kill us all in simpler ways, or even just lock us into an extra-paranoid authoritarian dystopia.
But the end could begin with a real asteroid mistaken (or misrepresented) for fake.