The problem of North Korea

As I see it the problem of North Korea is the problem of Kim Jong-Un. I can imagine that POTUS Trump believes that if he could take out the Korean leader (KJU), the generals might look for honourable peace by which I mean one in which they do not have to surrender.
But how to do it without triggering a huge overraction from KJU, destroying huge swathes of South Korea and possibly Hawaii. I can't believe that the CIA haven't already looked into assassination, indeed we will never know how many agents have already been liquidated by a paranoid regime acutely aware of the threat. Does anyone know where KJU spends the night, does he rotate addresses, for instance, or does he live in a MOAB proof bunker beneath his Presidential palace?
The cost of failure to kill KJU in any strike would be high but what of the benefits if successful? Apart from a global exhalation of breath in relief, Asia, including China, might feel the loosening of a noose from around their collective necks. The unification of the Korean peninsular would also be a prize worth the effort but one mustn't underestimate the likely cost in terms of lives lost.
While KJU is alive this 'loose cannon' could strike anywhere at any time. His missile failure today (16/4/2017) shows that his arsenal isn't yet as he would like it but what else does he have? Does POTUS wait and hope for some future accommodation or does he act now? Obama wasn't up to the job of deciding but is Trump willing to put US lives at risk? Did he come to some sort of understanding with the Chinese leader at their recent meeting? As ever, information and intelligence are key but with an actionman POTUS I don't think we'll have to wait long to see the outcome.