This doesn't make sense. Seoul is at risk because it is very close to the border where-as Pyongyang is much further from their mutual border.
There are, of course, other considerations, but Seoul would be very difficult to defend from 'simple' weapons like artillery. The US is very proud of it's ability to fire artillery 40 miles (64km), but Pyongyang is much further than that.
If NK attacks SK then the US will obliterate NK. The US does not need to use artillery to obliterate Pyongyang. Pyongyang cannot be defended against US weapons. Seoul and allies cannot defend against NK weapons.
This completely misses the point of the GP (or is that GGP) though. It's not a debate whether NK could survive, it couldn't, but Seoul is indefensible.
Everything I've read suggests the Seoul is a casualty of any conflict. Regardless of the eventual 'winner'.
Precisely this. There is no real winner in war (I'm a US Army Veteran of OIF II circa 2003-2004), only one side that might lose less. Taking a life breaks many people, even trained infantry. Look at all of the veteran suicides due to PTSD from war as proof of this.
Once someone on either side has been killed in war, both sides permanently lose. There are no take-backs, only damaged soldiers on both sides and casualties.
There is some work being done on shooting down artilery and mortar projectiles & Iron Dome deployed in Israel regularly shoots down small unguided missiles.
There are, of course, other considerations, but Seoul would be very difficult to defend from 'simple' weapons like artillery. The US is very proud of it's ability to fire artillery 40 miles (64km), but Pyongyang is much further than that.