TFA is literally about a $96 rocket.
> propulsion, warheads, arming and safety, QA, traceability, climate and shelf life stability.
You're entirely missing the point.
These do not need to be reliable for the scenario I hinted at. They also do not need to be armed.
They need to be large enough that if one of them is a higher quality rocket (not part of the $10k) that contains actual explosives, you have serious destruction on your hand. Maybe something that looks large enough for that will drive the cost up and we're talking $20k or even $100k instead of $10k.
The precise cost is largely irrelevant, as long as the total cost is a tiny fraction of the cost of a missile interception.
The point is you'd be multiplying the cost assymmetry by forcing a massively outsized response. Because if you don't try to intercept them, every future barrage will include a real rocket. If you do try to intercept them all, you'll be burning through massively expensive interceptors to take out a bunch of cheap toys.
If I was ever considering an insurgency, or a war, I'd be stocking up on vast quantities of toys, with the intent of making every radar constantly lit up by a number of possible threats.
> TFA is literally about a $96 rocket
It's a firework-grade rocket with no payload that can't even ignite reliably.
To imitate even a TBM or a MBRM, you need similar kinematics, even if you're running without a payload. Maybe your solid rocket motor would be a touch smaller because you're not delivering hundreds of kilograms of explosives, but it still has to be large because of the rocket equation. With a large motor you're looking at a lot of damage if it explodes at the launch point, so you need quality casting. You can't really save much money on the motor.
Then, you need a TEL. Because the motor is large, the launcher has to be comparable to the real thing. You probably don't want to have two different vehicles, so you keep the same vehicle; it needs to be armed, driven around, and set for launch. Not that different from the real thing.
So you've done all of that, and then you realise that your empty warheads are too light and the missiles (or warheads, if you split) don't interact with the atmosphere in the same way as non-decoy missiles do. What's worse, modern radars are perfectly capable of noticing that and discriminating the decoys. All of that effort, and you didn't win anything. Might as well add the payload.
The US and the UK spent vast amount of money chasing exactly your line of reasoning with nuclear warhead decoys. Chevaline is a culmination of the effort, and it's retired for 30 years. In the end, relying on decoys doesn't really work, they are too expensive.
Fancier CPUs change very little of this calculation, because compute is a very little part of the cost to begin with.
> The US and the UK spent vast amount of money chasing exactly your line of reasoning with nuclear warhead decoys. Chevaline is a culmination of the effort, and it's retired for 30 years.
OTOH if you built a successful decoy system that is exactly what you would want people to believe.