I'm not sure why this was downvoted. North Korea officially cited Gaddafi and Hussein as motivations, as reported by The Telegraph back in 2016:

http://www.telegraph.co.uk/news/worldnews/asia/northkorea/12...

The BBC has run stories on it as well:

http://www.bbc.com/news/world-asia-37321686

I'm sure it's just one of many motivations, but it does seem to be at least one of the motivating factors.

Libya was diplomatic failure of epic proportions.

Furthermore the value of NK isn't the people, but the geographical position. It is a well known fact that China is amping up its projection of power, and using it to claim territory. Doklam is the most recent example. Furthermore I don't think China gives two shits about forcing people into doing what it wills. 25 million people is basically a negligible amount for China to handle, it's >2% of their total population. If anything it is an opportunity to gain goodwill by "rescuing" them.

All I'm saying is that perhaps China has a vested interest in trying to provoke NK into increasingly irrational decisions so to open an opportunity for them to annex NK in the name of "maintaining order".

Libya was failure of aggression. Where was there diplomacy happening? Hillary Clinton's quotation on the diplomacy was, "We came, we saw, he died."

https://www.democracynow.org/2016/3/3/the_libya_gamble_insid...

Libya was a failure of President Obama to honor a deal made by President Bush.

Qaddafi gave the U.S. his centrifuges and other equipment, which in turn laid bare the A. Q. Khan network and Iran's program, and also helped the U.S. and Israel hack Iran's program to slow it down. And just what did Qaddafi get for his troubles? He got killed.

After that betrayal no one will make any deals like that with the U.S. again. To say that President Obama's Libya adventure was destructive is to put it mildly.

Or perhaps, the US has a vested interest in a divided and unstable Korea to have an excuse to maintain lots of military bases in the region, because China. And Russia.