After conducting a record number of missile and nuclear tests in 2016 and 2017, North Korea dramatically changed its policy approach and embarked on a diplomatic initiative in 2018. It announced a self-imposed halt on missile and nuclear tests and held summit meetings with the United States, China, and South Korea from spring of that year.
Why did North Korea shift its policy approach? This paper evaluates four alternative explanations. The first is that the change was driven by North Korea’s security calculus. In other words, North Korea planned to achieve its security goals first before turning to diplomacy and successfully followed through with this plan. The second is that U.S. military threats forced North Korea to change its course. The third is that U.S.-led sanctions caused North Korea to shift its policy by increasing economic pain on the country. The fourth is that diplomatic initiatives by South Korea and others prompted North Korea to change its position.
This paper examines the actions and statements of the United States, North Korea, China, South Korea, and Russia leading up to and during this period to assess these four explanations. It concludes that military threats and economic pain did not dissuade North Korea from obtaining what it considered an adequate level of nuclear deterrence against the United States and that North Korea turned to diplomacy only after achieving its security goals.
External pressure may have encouraged North Korea to speed up its efforts to develop the capacity to strike the United States with a nuclear-armed missile, the opposite of its intended effect. Diplomatic and economic pressure may have compelled Kim Jong Un to declare that North Korea had achieved its “state nuclear force” before conducting all the nuclear and ballistic missile tests needed to be fully confident that it could hit targets in the continental United States. These findings suggest that if a pressure campaign against North Korea is to achieve its intended impact, the United States has to more carefully consider how pressure would interact with North Korean policy priorities. Pressure should be applied only to pursue specific achievable goals and should be frequently assessed for its impact.