The problem with sanctions is, it assumes there is something the North Koreans want more than they want nuclear weapons.  But there isn't.   What they want more than anything else is useable nuclear weapons.  They want useable nuclear weapons more than they want money, or trade, or food for their people.   That's why sanctions probably won't work.   And that's why, in my opinion, there are two possible outcomes: either they get nuclear weapons mounted on ICBMs and we adopt a policy of deterrence, or this all ends in a very violent and very bloody and very expensive war.  There's just no way we are going to persuade them to stop what they are doing.

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