North Korea claimed to conduct a successful underground nuclear test in the northeastern province of North Hamgyong on Feb. 12. While it is not yet clear what sort of device North Korea tested, initial estimates suggest a 6- to 7-kiloton yield, which is slightly larger than past North Korean tests. Prior to the test, it was suspected that the North would test a uranium device following its two earlier plutonium tests. This would mark another step in North Korea's nuclear program, though North Korea has long been known to be working on a secondary uranium program, and in some ways a nuclear reaction with uranium is technically easier to effectively detonate than a plutonium reaction. It also could be a third plutonium test, as North Korea continues to refine its nuclear program and work toward a viable nuclear weapon, as opposed to just a nuclear device. Although Pyongyang has pursued a strategy of survival based on presenting a fearsome, irrational yet weak image, the North views its nuclear and missile program as more than just a bargaining chip. Pyongyang is pursuing what it considers a viable deterrent: a weaponized nuclear device that can fit on a missile. This deterrent would not be necessary for North Korea's neighbors — they are already within reach of North Korea's conventional weapons — but instead would be directed at Washington, even though a small number of nuclear missiles would not significantly threaten the United States. Pyongyang also sees in the program a way of removing its dependence on China. Pyongyang has sought an independent deterrent in order to feel confident enough to either open direct talks with the United States to bring a final resolution to the armistice in place since 1953 on the Korean Peninsula, or to simply move forward with domestic economic experiments without the fear of U.S. interference.