North Korea's conventional military power is fading:
North Korea has, over the last decade, lost most of their conventional military capabilities, especially relative to South Korea and Japan. This trend accelerated after 2010, when Kim foolishly ordered a South Korea island, near the west coast sea border, fired on by his coastal artillery. The island had a civilian population as well as a military garrison and there were casualties among both as well as property damage. South Korea retaliated in the most damaging (to North Korea) way possible. Instead of counterattacking, South Korea changed its fundamental attitude towards North Korea and revamped its military and diplomatic attitudes towards the north. From then on North Korea was definitely the enemy and had to be treated as such. ...
In the last decade even the North Korea special operations troops have lost much of their specialness. Only about 20 percent of these troops retain their “special” skill levels. That does not exempt them from the electricity shortages and the knowledge that the rest of the military, and most North Koreans in general are in worse shape.
I've long noted the decline of the North Korean military threat, and believe the decline gives South Korea the opportunity to operate north of the DMZ to shield Seoul from North Korean artillery bombardment:
North Korean forces once loomed over Seoul prepared to drive South Korean and American troops south and capture this vital hub of South Korea that contains a quarter of South Korea's population. Times have changed radically.
As North Korea's military has eroded along with the state that built it following the collapse of their sponsor the Soviet Union, the threat from North Korea has moved from conquest to mass murder.
North Korea seeks nuclear weapons to restore the correlation of overall forces by putting all of South Korea at risk of destruction. That, they hope, will deter the increasingly superior South Korean military from moving north.
Now North Korea has to rely on the destruction of Seoul with conventional and conventional artillery to do that job.
Honestly, that's probably enough to get South Korea to leave North Korea alone.
But South Korea is gaining the capability of operating north of the DMZ.
Years ago, I speculated that South Korea would naturally want to carve out a no-launch zone north of the DMZ to gain the ground from which artillery could pummel Seoul.
If North Korea has sought nukes to preserve their regime (with their military rotting away and sadly for North Korea's plans, even the secret police are becoming corrupt and so less reliable defenders of the regime), banking everything on those nukes actually guarantees they'll have to use nukes to defend themselves--which will result in the nuclear destruction of the regime.