North Korea has claimed that its new submarine has nuclear attack capabilities, which would allow it to counter the United States and its Asian allies. However, South Korean officials are skeptical of the submarine’s capabilities and believe it is not ready for operational duty. The development of the submarine highlights North Korea’s efforts to extend the range of its nuclear arsenal with harder-to-detect systems. Analysts say it would still take considerable time and resources for North Korea to build a fleet of operational submarines. Russia’s assistance could be helpful, but it is uncertain if Moscow would share its sensitive technology.