North Korea is being very consistent in pursuing what they believe with give them "self-reliance in defence" in that they will not have to rely on any other country for their own defence (such as China). Its part of their official ideology (set out in Kim Jong Il's "On the Juche Idea", effectively like a North Korean bible if you will). Its pretty disturbing for us because of the way the North Koreans view the role of emotion and propaganda is they want a nation of fanatics who will fight to the death for their cause. Its based on the principle of "if we are crazy enough, no-one will mess with us" and draws conclusions for the success of guerrilla movements in like the Vietnam War beating conventional forces and a technologically superior enemy (i.e. the USA). If you have a nation ready to die in battle, no matter how good your tanks are- you're pretty screwed just because of the sheer numbers against you. Their propaganda should be viewed largely as for internal consumption and not necessarily for our benefit. (e.g. the proposed attack on Guam was probably about showing north koreans that they can defend themselves from a position of "strength" and are closer to the goal of "self-reliance").
Still, We aren't use to that kind of"ethic" wielding nuclear weapons (for obvious reasons). What they lack in technology, they are trying to make up for in hyperbole to keep the people stirred up. They've been preparing for war for over fifty years, such as building munitions factories underground to protect them from bombing raids. The probability is they won't launch a first strike against the US or anywhere else, but its not certain. Kim Jong Un isn't a psychopath as there is "method in the madness"- but what the North Koreans are doing is so alien to our way of thinking that it definitely
looks crazy.
The PDF below may help explain "WTF the north koreas are doing" if you are interested.
http://www.ckquinones.com/wp-content/uploads/2008/08/Maison-Franco-Japonaise-Juche-Paper.pdf
