Well folks, it looks (preliminarily atleast) like North Korea has successfully tested a nuclear device, probably somewhere in between 10-20 kilotons of yield at about 00:54:43 UTC. It looks like it was located in the North-Eastern part of the Korean Peninsula. The USGS detected the event, details at:
This apparently successful test indicates that North Korea may have processed their reactor plutonium more creating a true weapons grade material--in otherwords they solved the predetonation problem---if this was a plutonium device.
Personally I would wait for verification from radioactive residue before I made a determination. But assume the pundits are correct-fine ...so what's the big deal?
N.Korea obviously wants market access now that they're a member of the nuke club. Ok, so Japan and S.Korea military would want nuke weapon to counter a possible threat ...fine both Japan and S.Korea could assemble an thermo nuke explosive device in less time they obviously have the capability to do so.
What effect does Japan and S.Korea pursuing nuke weapons on 6 party talks?
Not much.
Just means everyone sitting on 6 party talks would be members of the nuke club.
Now everyone is on equal ground and can talk business like LWR reactor contracts etc. maybe NPT and other issues.
Maybe the result could be opening markets for the region.