Well the UN has voted for sanctions.. and as china voted for them too then they should actually have an effect. We'll see exactly what that is though, and how long it takes.
Nuclear weapons are a weapon of last resort. NK havng nuclear weapons in no way represents a threat to the USA. UNLESS the USA decides to invade NK in some crazy attempt to prove something. And deciding to go up against an army twice your size, with nukes, is pretty crazy imho.
KJI wants nukes so that the US can't ever preeptively assault him like they did saddam. (NB: "that fool Saddam didn't update his military" because he wass busy complying with UN resolutions and destroying all his missiles.).
He also feels they will boost his standing and negotiating power within the asian region (mostly with south korea and japan).
Since the only chance of him using them (baring an acciednt that wipes out half of one of their cities) is attacking him.. it seems strange that your ideal response to him having them should be "attack!".
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