By HYUNG-JIN KIM and KIM TONG-HYUNG
SEOUL, South Korea (AP) — North Korea’s recent sword-rattling after months of relative quiet makes clear that leader Kim Jong Un is working on expanding his weapons arsenal. Nuclear-capable missiles hidden in trains that can be launched anywhere along a railway. A new cruise missile that can be potentially topped with atomic warheads. The apparent resumption of making fuel for potential nuclear bombs. Likely they are an attempt to wrest concessions from Washington if, and when, long-stalled diplomatic talks on Kim’s nuclear program resume. Part of the message is aimed domestically, however, to reinforce internal unity as North Koreans cope with deeper hardship in a never-healthy economy that’s been battered by the coronavirus pandemic.