Signs of that system breaking down have appeared. Now the signs are really bad:
Senior officials of the secret police (NSA, National Security Agency) have been arrested for taking bribes to enable people to escape to China. This is unprecedented, as the NSA is considered the ultimate guardian of the North Korean government. But for the last few years, a growing number of rumors described many NSA officials as "approachable" (could be bribed.) Four months ago, North Korea sent agents from two competing agencies (military intelligence and the NSA) to help fight corruption along the border. The agents were ordered to watch their rivals for signs of someone being bribed.
As the title to that post says, "this cannot be good."
The nukes haven't really shown up, despite some partially successful nuclear tests of nuclear devices (not weapons). And the spooks aren't all that loyal, it seems. The kooks are getting lonely at the top.
The next stage will be a reliance on just some of the spooks to protect just some of the elites from everyone else (the real 99 percent). This ends with some of the elite hanging from dark lamp posts in Pyongyang's central square.
Well, it will begin that way. Who knows how it ends?