Can't do nukes, for sure. Too close to China. I think they're doing the right thing by going ahead with this weekend's US-SK naval drills in the same area as the attacks. That great big-ass aircraft carrier is a good way to broadcast to the watching world that NK will definitely lose any war it gets involved in. I see it as a kind of 'put up or shut up' statement to the NK brass. Now the question is whether or not the NK brass are going to respond with pride or pragmatics. If they're proud, they'll fire off a few more artillery shells and get pounded into dust, which will escalate, etc etc. If they're motivated by pragmatics, they'll sit on their hands and live to fight another day. I'm pretty sure the latter will happen, but I secretly wish for the former.
Honestly, the best course of action, IMO, is to blockade the north and force them into a conclusion, peaceful or otherwise. They can't survive on overland, cross-border commerce with China alone. The diplomatic appproaces and economic sanctions I've seen so far have just been thinly-veiled admissions of powerlessness by the UN and the West in general.
One more thing: there's no evidence that NK has weaponized its nukes yet for any range of missiles. It's just a matter of time before they dy. One way of looking at it is that the window of opportunity is closing for dealing with a (practically speaking) non-nucular North. IOW, it's not going to get easier; it's going to get harder.