We don’t really know what is going on behind the scene so any comment I make will be an uninformed one.
Overall it appears some progress may have been made but we all should have known it would be a long process.
Our relationship with North Korea reminds me of my relationship with some feral cats that adopted my back yard.
They allow me to feed and water them and give them an occasional treat but we are not close enough for me to pick one up .... yet. I am the US in this relationship and big enough to harm them if that was my intention. They on the other hand while smaller have very sharp teeth and claws and could do me some harm if that was their intention. Negotiation between us occur daily and progress is slow.
My three cats will never be house cats, and neither will be North Korea.
Better strategy even if it ultimately is unsuccessful.