Yeah, my interpretation is that the Feredation, being a bunch of fascist twits, didn't act to intercept the asteroid. And then, since you never let a good disaster go to waste, they blamed it on the bugs and just piled on propaganda to silence anyone who pointed out how silly and impossible that is.

Later on they show the big space artillery guns that can destroy asteroids, sort of a cya thing.

Do you think the Klendathu sequence where the Arachnid's surface to orbit planetary defense batteries are shredding the federation space ships should be viewed as part of the propaganda, or a more "real" sequence that shows all the fascist bravado and machismo breaking down. Like they're now facing the enemy for real, and shocked to find out that their enemy isn't as weak and pathetic as they believed. Same with the actual ground battle, where you see the propaganda camera crew get shredded. I wonder if that should be viewed as part of the framing narrative propaganda video, or as a place where the fascism beliefs break down when confronted with reaity.