Attempts to negotiate with the DPRK authorities by diplomacy methods, in my opinion, are doomed to failure, since the DPRK authorities, in fact, deliberately use their nuclear missile program as an instrument of blackmailing the Western countries. The goal of the DPRK authorities is to use blackmail, “carrot and stick” methods to weaken economic sanctions and possibly receive humanitarian aid for North Korea.
I see one way to stop this activity of Kim Jong-un: an active information policy, delivering truthful information to the people of the DPRK. To do this, autonomous drones with loudspeakers can be used, which will spread anti-government counter-propaganda in a fairly large territory of this country.
In modern international law, the attitude to the "information war" is not defined. It can be assumed that international standards do not prohibit such a war. This can be illustrated by the example of another authoritarian country whose authorities act irresponsibly: Venezuela. Obviously, international standards prohibit the bombing of Venezuela by US aircraft; however, no one forbids “bombing” the Venezuela with humanitarian aid boxes along with leaflets, or for example gadgets that pick up satellite Internet.
The Achilles heel of authoritarian regimes, such as the DPRK, is that anti-government counter-propaganda may relatively easily lead to a popular uprising against the government, since official propaganda by the authorities misleads the population. North Koreans live in an “artificial reality” in which US residents receive food on food cards. A significant part of the Venezuelan population also lives in a world of illusions, for example, it believes that the World Bank is to blame for inflation in this country. Counter-propaganda should destroy such illusions with arguments.
My words may seem shocking, but it’s important for me to convey this point of view to the reader: I believe that if the government of Kim Jong-un in the DPRK begins to lose power as a result of counter-propaganda, and it will launch a nuclear strike on South Korea or Japan in attempts to maintain power - this will prove to be useful for humanity in the long run, since humanity in this outcome will receive an important lesson and will be aware of the global danger of irresponsible authoritarian regimes. Nuclear weapons might get replaced with something even more dangerous, and if humanity does not become more responsible in general, it will destroy itself.
Currently mankind is like a small child, who cannot comprehend that he can’t touch the hot iron - only by touching and burning himself once, he will draw this conclusion. It is hoped that over time the humanity will become more mature.