How the US could respond to North Korea's nuclear threat

A US MGM-140 army tactical missile is fired during the combined military exercise between the US and South Korea against North Korea on Wednesday.Public urgency about the threat of North Korea developing a reliable long-range nuclear weapon capable of striking the US was sharpened by news of what Pyongyang and outside analysts say was a successful intercontinental ballistic missile test.Any immediate US response must take into account the ability of North Korea to instantly launch a devastating