What damage would it do? Would North Korea’s relative backwardness help it?
Is it possible to target Pyongyang without harming China or South Korea
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NK’s backwardness is probably not much help. It’s military still relies to a certain extent on technology to mobilize.
Your second statement though is the show stopper. While a weapon could be deployed that would hurt NK and not physically harm China it would certainly rouse some serious political/military backlash from China.
It wouldn’t stop NK from leveling Seoul with its thousands of dug in artillery pieces.
I’m pretty sure modern artillery is dependent on electronics. I doubt they’ve got a bunch of fully mechanical artillery pieces.
Would the artillery not even be able to fire without their electronics?
I would assume not, though Stranger on a Train pointed out in another thread that all US military hardware is designed to resist radiation to some degree. Wven if it worked, I doubt they’d be able to aim the guns though.
Classic tube artillery is laid and fired pretty much manually, below a certain size. So artillery CAN be non-electronic. Don’t know if the long-range stuff you’d use to blow up cities would be, but since I’m sure Seoul isn’t evading, NK wouldn’t have to do much on-the-fly targeting. I would guess that the weapons allocated for that purpose are already aimed pretty precisely where the need to be aimed. Just load, lock breech, and pull the lanyard.
If the shells were electrically fuzed, I wonder if that would be a problem. OTOH, if they’re just bombarding a city, I wonder if they’d be electically fuzed?