Obstacles to a Deliverable North Korean Nuclear Warhead

While the recent Defense Intelligence Agency assessment that North Korea has mastered the miniaturization process highlights recent advances in North Korea's nuclear weapons and missile program, a number of key technological obstacles remain before Pyongyang can field a reliable nuclear arsenal. Even if North Korea has in fact constructed a nuclear device small enough to fit into a ballistic missile, that does not guarantee that the nuclear device — or the ballistic missile for that matter — would survive re-entry into the Earth's atmosphere or detonate at the desired time, place and altitude.