What is your opinion on the assessment made by the "expert"?
Such an ignorant assessment by a so-called "expert." His premise assumes that mutually assured destruction which has prevented nuclear war between the super powers in the past applies to the N. Korean situation. That premise is untenable as Kim Jong Un views himself as God-like (and therefore invincible). At the very least he is mentally unstable. Diplomatic negotiations with a mentally unstable person is an exercise in futility.