NK has taken advantage of 1- US patience/donothing, and 2- US refusing to negotiate unless NK agreed first to give up its Nuclear Arms program. Both 1 and 2 just gave NK more time to develop weapons. Time is on NK's side to keep perfecting weaponry and eliminate fear of a US attack. To NK, Trump looks a lot like prior Presidents-- noise, no action, and bluffing about action like sending a Carrier to Korean region. US should have private talks with China on 1- Economic pressure, and 2- what we would expect from negotiations with NK on its Nuclear Program, and what we would give NK to get such an agreement--carrots to go with the stick (keep yalks secret and see if China can get an agreement to negotiate). China would need to convince NK that they should ignore Trump's tweets about China-- so China is credible in suggesting acceptable terms for negotiation, and let them know that China will impose tougher sanctions and support US sticks. but offer carrots with US after final agreement.