Motives

With countries like North Korea it seems like the only reason they want to possess Nuclear Arms is because they know that most other countries DO NOT want them to have them! They ensure that people will continue to trade with them and such, by scaring them not to. No country is going to cut off communication with them as then they will simply attack them. As I have previously mentioned they did in fact once sign the Nuclear Non-Proliferation Treaty, they then backed out of it. They most likely backed out as they saw the opportunity to do as I have stated above.