This constant saber rattling on both sides will eventually result in a WAR!  North Korea has said before that they want to hold talks with the U.S.  The U.S. however wants NK to stop nuclear development before the talks.  The U.S. stance doesn't make sense.

The U.S. with China, Japan, and South Korea needs to hold high level talks with North Korea.  Work to end the North-South war and create a treaty.  Then extend a "carrot" to the North - economic development assistance in return for an end to nuclear weapons development by the North.