Existing theories of coercive diplomacy logically pinpoint missing elements in the negotiating process and resulting outcomes concerning North Korean issues. They do not, however, explain why we have failed to obtain the elements crucial for influencing North Korean leaders’ perceptions. This paper claims that a lack of will to actually retaliate against North Korea is responsible for the successive failures to deter North Korea’s repeated limited-aim attacks, not a lack of capability. The author argues that credible intimidation lies at the core of “Proactive Deterrence.” Case studies in this paper also show that inconsistency in policy toward North Korea should be considered an important factor in the failure to coerce North Korea to abandon its nuclear program. Factors of domestic politics and ideological confrontation in South Korean society are also analyzed as part of several popular but flawed arguments concerning inter-Korean relations. In addition,the author assesses the current status and forecasts the future of the North Korean regime, a key factor in the inter-Korean relationship,the ROK-U.S. alliance, and future U.S. Northeast Asia strategy.