First, President Trump is committed to a North Korea without nuclear weapons, albeit some backsliding on the matter may be in the discussion, particularly the time-table.
Second, North Korea claims a treaty with South Korea ending the six decades of hostility could be attained. The question is at what cost.
Third, North Korea has demanded a nuclear-free Korean peninsula which probably means the removal of the U.S. nuclear umbrella from South Korea and beyond.
Fourth, there are regional considerations at play including the role the U.S. will have in offering modest protection to nations in the Pacific basin.
Fifth, the North Koreans are demanding the lifting of sanctions before any serious discussion of nukes can take place.
Sixth, economic development in the North is a prerequisite for these negotiations. But the other side of the equations remains murky. What is North Korea prepared to do in order to satisfy their rivals on the other side of the DMZ?
Seventh, Kim Jung-un has demanded security for his nation and himself. However, if genuine reform occurs, the likelihood of regime change increases. Can Kim have it both ways?