What is NK's goal? They know perfectly well that to launch a nuke against another country, especially the US, could result in NK being entirely obliterated. ~30 mostly little cites: https://en.wikipedia.org/wiki/List_of_cities_in_North_Korea How far along has this strategy been considered?
To preserve its sovereignty, and preserve the inflow of foreign aid that the regime uses to prop itself up by preventing the starvation and likely resulting chaos that'd occur if forced to try to support its population from its own ill-managed resources.
I'm sure at least someone close to Kim knows that to actually nuke an American city would invite massive retaliation. But seeming plausibly crazy enough to do it anyway is a good way to make an otherwise absurdly insignificant little country seem like one that needs to be reckoned with. They're banking on the idea that the US will go far out of its way to avoid even the remote possibility of even a minor nuclear strike, and thus far it's worked out for them.
They know if you're going to obliterate their country anyway, they have a little present for you. And you know it too. That's how nuclear weapons work.
The North Koreans have no hope of beating the South in a conventional conflict. Strategically, they're in the same situation as Pakistan, which acquired nuclear weapons as a guarantee against an attack from India.
The Norks have also gotten a lot of mileage from their blackmail/bullying behavior over the years. They may be calculating other countries will be willing to make concessions to keep the crazy guy with nukes quiet.
Does NK as a country have any goals? I think it is more just the few at the top just want to stay at the top, and play whatever games they deem necessary in order to do so.
Everything that NK does is in order to keep those people at the top. It is the absolute definition of a dictatorship. Kim Jong-un only wants to maintain his own wealth and control. That is the only goal
It's too simple view to be true. For one thing, Kim Jong-un understands that if he's not in control, he and his family members are dead. Of course, they want to maintain wealth and control, just like everyone else. But they also don't want to become dead. And they're dead in either of situations:
To preserve its sovereignty, and preserve the inflow of foreign aid that the regime uses to prop itself up by preventing the starvation and likely resulting chaos that'd occur if forced to try to support its population from its own ill-managed resources.
I'm sure at least someone close to Kim knows that to actually nuke an American city would invite massive retaliation. But seeming plausibly crazy enough to do it anyway is a good way to make an otherwise absurdly insignificant little country seem like one that needs to be reckoned with. They're banking on the idea that the US will go far out of its way to avoid even the remote possibility of even a minor nuclear strike, and thus far it's worked out for them.