North Korea is close to a nuclear weapon and they proved that today when they fired that long range missile. We need to make sure that they are not going to use this technology for bad things. They will continue to make bad decisions unless we can counsel them to not.
I believe the evidence points to them already having nuclear weapons capability. My understanding is, they just need to figure out how to make the bombs small enough to mount on a long-range ballistic rocket. My concern is that they have now shown the ability to launch these rockets. Which part seems harder to you?
In order to believe they are close to making a nuclear weapon you would have to ask yourself why they would want one. They are an extremely poor country with little position or authority on the world stage, and they rely on aid from other countries to survive. I don't think the other nations in the world are much concerned about this, we have already seen the US military go into one country suspected of having weapons of mass destruction, and the US would probably easily go into North Korea if we suspected them of being close to having nuclear capability.
Do I think that North Korea has created a Nuclear missile...yes, but they lack what is needed to have a real weapon. People do not realize that if North Korea decided to set off their largest nuclear weapon at the Empire State Building, it wouldn't be strong enough to reach Central Park. The truth is that they are a very long ways away from having a true weapon that we should fear. Their society is very unstable and it is hard for them to recruit scientist that could help them develop weapons that would cause us to fear. Instead North Korea uses these "weapons" as a way to negotiate for aid for their country. North Korea would have to face the wrath of the US, China and Russia if they decided to use nuclear weapons. There is no real way they could win if they really made a weapon.