They have nuclear capabilities but the ability to attach those to long range missles is in question. They can't attack the US (the actual country I mean) directly, but they could attack S. Korea or one of our bases in the Pacific. Since S. Korea is an ally it would be tantamount to attacking us as we would pretty much be obligated to defend them. But any nuclear attack would bring down most of the international community on them as well.
It's not a "nuke threat" yet, were not all in defending S. Korea (there real enemies) so if they directly threaten us or attack us then we would step up our defenses there and declare war on them and ultimately delay them from achieving their real goals. You don't have to worry my friend :) even if they could bomb us it would ultimately destroy their country and they know it
I've been under the impression we have a shield and defenses for such an attack I myself am not too concerned about these fools they would be signing off on their own destruction its very stupid shooting at a bunch guns that are pointing at you but they are stoopid . whata ya say? SCREW EM (up).
I think he'll order a few lobs at more islands around South Korea. That's all he can do, considering his limited arsenal. But he'd better tread verrry lightly. Too much to lose. He's already made his people suffer UN Sanctions. Even China is shaking their head at him. If he has any sense, he'll backstep and quiet down. I feel for the people.
We have a missile defense shield located in central coast of California with about a 3000 mile kill radius. That's enough to cover all of the west coast, and most of the northern and western states. A polar insert would have a very small window to hit the US, and with the addition in 2015-17 of 14 interceptors in Fort Greely, Alaska, that window would close. Additionally, our fleet has been testing a THAAD (theater/terminal high altitude air defense) to be integrated with NMD. Today, NorKor can't fuel and fire enough missiles to make it past our defenses, but they can hit other countries; this is why China has to reign in the bully on the block. We could always punish China by removing their most favored nation status on trade; that would likely be enough to bring them down on NorKor.