I often wonder that what if North Korea were to be recognized as normal legitimate nation 

by U.S.. If North Korea has normal diplomatic relations with U.S., South Korea, and other nations, 

she will have commercial trades and earn the foreign currencies legitimately.
 

The fundermental reason for nuclearization of North Korea is because U.S. placed more than 

1,000 - 2,000 nuclear heads in South Korea until early 1990's. Perhaps, Kim's behavior is the reaction

to the action of U.S..That does not mean that he wouldn't collect the money for himself illegitimately.