I don’t know why an artillery barrage must kill millions. Don’t they have any place underground to hide? I mean, certainly the first salvo would be very bad but I think people overestimate the casualties.
I’ve been to Seoul. It’s very tall, and very dense. 30,000 shells fired would cause tremendous damage very fast. “Millions dead” might be excessively pessimistic, but is within the scope that must be considered.
I never understood this either. With a few minutes warning can’t many or most people take adequate cover? I understand this would still be deadly but not anywhere near a million.