North Korea uses their Nuclear Stockpile to sustain their stability in the world stage. The Nuclear weapons are to keep the US at bey, as well as giving off a possible threat of 'nuking' South Korea or Japan to keep their stance on Global Power. North Korea wouldn't dare to launch a 'ICBM' or Nuclear Weapon at the US. However, the US fear of North Korean nuclear usage would keep the US from directly conflicting NK. As well as keeping the Kim Regime standing.