Regardless of its relative success or failure, the recent nuclear test by North Korea resulted in calls from all sides for that country to cease its nuclear armament program. The foundation for all of these calls is the Nuclear Non-Proliferation Treaty (NPT). The NPT, which is binding in international law on all nations, not just its signatories (see 1996 ICJ advisory opinion), requires that non-nuclear states not pursue the development of nuclear weapons. So, clearly, North Korea had no right to develop a bomb, let alone test one. It says so clearly in the NPT, which is binding, and must be respected...
Of course, what we aren't hearing are the cries that the NPT also says that the nuclear powers must disarm. That isn't very convenient, especially with the US Department of Energy working on developing a new generation of smaller and "more useable" nuclear weapons. Yes, the second pillar (article VI) of the NPT, right after non-proliferation, is disarmament. And the 1996 Internatinal Court of Justice advisory opinion also made it clear that this obligation to disarm--to conclude and enact agreements resulting in actual disarmament, not just to enter negotiations--is equally binding on all nations under international law.
Quite the sticky wicket. The US is equally in violation of international law by not disarming as North Korea is by creating a bomb and testing it. Funny, then, that we're only talking about enacting sanctions on North Korea. International law is normative, not rule-based. That means that it only has effect by the standards created for nations by the cumulative actions of others. So the UN or the US can say all they want that the North is in violation of international law. This is only true to the extent that such normative law exists, and because all other nuclear powers are flaunting their obligations under the NPT, it's words do not rise to become normative. Therefore there is no norm--and hence no law--for North Korea to violate. All talk to the contrary is just that. Likewise with Iran. I'm sure we will hear people discussing how Iran is violating international law as well. As soon as those same people point out how the US and France and China are similarly violating that law, then we're getting somewhere. Until then, talk talk talk.
What to do? That one is easy in my book. Disarm. Unilaterally. It's not like we can really use those nuclear weapons anyway. Ignoring for the moment the argument that none of our missiles could even get out of their silos without a month's notice, we stand to lose virtually nothing, and we stand to gain so much. Disarm unilaterally, gain the respect of the world, create a true normative environment to bring pressure on what will only then actually be "rogue" states to meet their own obligations. Obligations that in a normative system will only then really exist. Disarm unilaterally and gain the moral high ground. Or, continue with our hypocritical ways and see how far that gets us. For a change, it really is our choice.