North Korea is not an insane nation. It is not a crazy nation.
We have received a variety of messages from North Korea in recent months and it seems to me that the general thrust is that they would welcome a visit by assistant secretary (James) Kelly,
I would not suggest the U.S. should sit down with the North Koreans bilaterally immediately after they've fired missiles - because the appearance is that you reward bad behavior. But if North Korea behaves for some period of time, I would pretty much favor direct talks.
On the question of whether we will have missile talks about missile defense with North Korea -- right now, we are not talking with them about anything, but I suspect in the near future we will,
North Korea is one of the major proliferators and it appears that they are busy proliferating again,