If it is north Korea how should we respond? Besides all the obvious ones (e.g., sanctions, statements of condemnation) here are a few for consideration.There are four major diplomatic, economic/financial and military actions that can be taken to have a significant impact on Kim Jong-un's authority and the ability to keep the regime together.One is to focus on the financial aspects of the regime's illicit activities and reprise the Banco Delta Asia actions but on a scale even greater than the $25 million. Of course this would take Chinese agreement and tacit support.The diplomatic action would be to persuade countries around the world where north Korean diplomats are conducting illicit activities to enforce their national laws and at a minimum declare them PNG and have them sent home or on the more extreme end incarcerate them for breaking national laws as they participate in drug trafficking, counterfeiting, and other illicit activities while hiding behind their diplomatic immunity. The specific focus would be on Department 39. Effective intelligence sharing and law enforcement activities could cripple the regime's ability to gain hard currency which could cause a loss of support among the regime elite and bring the regime to its knees.The third action would be an aggressive enforcement of the Proliferation Security Initiative (PSI). Diplomatically the US should request all contributors to PSI to conduct enforcement actions together with the US to interdict the north's proliferation activities around the world which would also cut off the flow of hard currency to the regime as well as military material flowing to other bad actors.The fourth would be to conduct cyber operations against north Korean commercial interests (illicit and front organizations) around the world (again this would reduce regime access to hard currency and resources). Or as an alternative directly target the nKPA's hacking units and try to shut down their access to the internet (if that is possible).These are some specific ways to get at the center of power of the regime and possibly influence regime behavior by creating a very painful existence for the regime and its elite.