The United States has a problem in the Pacific. North Korea, an old school Stalinist family dictatorship, is a nation openly hostile to the United States and is a hostile power to our allies in region, including its immediate neighbor South Korea, with whom North Korea is still technically at war.
Without going into the details of the Korean War, let it suffice to say that armistice peace has been maintained for several reasons since the war. First, North Korea, despite all its aggressive talk and saber rattling, is not an expansionist state. While it would like to unite the Korean people under its rule, the regime has largely confined itself to controlling its own people. Second, China, which certainly has global aspirations of superpower status alongside the United States, does not view North Korea as a threat to its interests and therefore sees no urgency to intervene in its foreign entanglements. Finally, South Korea, a prosperous modern nation-state, has no interest in war that could destabilize its economy, cause a mountain of destruction, and see millions of refugees (and agitators) into its territory.
So, what exactly is the problem with North Korea having nuclear weapons? First, Japan. Obviously, given the history, Japan does not want to negotiate with a dictatorship under the threat of nuclear weapons. Second, the United States, given its array of naval and military forces in the region, also does not want to negotiate with such a state.
But you know what? We're gonna have to live with it.
First, North Korea so far has indicated that it is not an irrational power, despite the avalanche of crazy talk they regularly spout. There's really no reason to think a strategy of deterrence and containment won't be as effective as it has been with other nuclear armed states. This may very well mean the United States moving nuclear weapons into the region over Chinese objections.
Second, even a limited military strike by the United States on North Korea would be catastrophe. It would almost certainly lead to a second Korean War and it would be a brutal, bloody conflict with significant loss of life and widespread destruction. Including the possible use of nuclear weapons by North Korea and submarine based nukes by the United States. This would be a complete disaster with devastating implications for the global economy and order in the Pacific. North Korea is not some podunk Middle East fiefdom like Yemen or Syria or Somalia. They'll destroy a lot of stuff and it won't be easy to defeat that regime and its likely Chinese support without a full on air, sea, and land war.
Obviously, there are folks who may believe we can destabilize the regime to bring about internal collapse, but there's really no evidence to support that the Kim regime's grip on power is in any way unstable. Furthermore, it isn't clear that this is even a desirable outcome due to the large number of refugees likely to flee into both China and South Korea.
I think those who say the escalating sanctions policy has failed are correct.
So, we won't be able to get North Korea to give up its nukes. The Chinese don't view the nukes as their problem so they won't do anything about it (and most analysts doubt they could). We can't collapse the regime. And war is not an option on nuclear power that, while hostile, is not expansionist.
So what's that leave us with? Welp. It basically leaves us with having to live with a nuclear armed North Korea. Like we do now. Perhaps its time to accept the inevitable and negotiate directly with Kim. Diplomacy is the only reasonable path forward here so we may as well get on with it.
The real problem with that? US domestic politics. No matter which party faces the facts, the other party will bash the hell out of them for it. So any kind of strategy to negotiate with North Korea in a bipartisan fashion is likely to be difficult to engineer.