The North Koreans have been milking the TV news for coverage of their upcoming rocket launch. If they launch and put a satellite into orbit, they will gain enormous amounts of respect. A rocket good enough to throw a satellite up is good enough to throw a nuke anywhere on earth. Say like into Washington DC.
Fox TV has been calling the North Koreans a nuclear state. That is an exaggeration. The Norks have run two tests, both of them fizzled. Yield was so small that observers waited to detect airborne radioactivity before announcing that a nuclear test had occured. Clearly the Norks haven't figured out how to make a fission bomb that really explodes. They have undoubtedly made some engineering changes to their bomb, but until they can run off a test with the same yield as leveled Hiroshima 65 years ago, they ain't a real nuclear power.
The Japanese and the South Koreans are seriously worried about a North Korea with missiles, and have threatened to shoot it down. This is a gutsy move. If they shoot and miss (fairly likely) they just look foolish and loose more face than if they just send nastygrams to the North Korean foreign ministry.