A very well-placed government source told me Tuesday afternoon that the North Korean explosion was non-nuclear. The explosion may have been an actual nuclear test — this is unknown — but the source reports the outcome was non-nuclear. The source stressed the importance of bearing in mind that though the explosion occured in North Korea — if it was actually a test and not merely a dictator clamoring for attention and influence — the test may have been by or for the Iranians. The source reported that American physicists with access to the information see no sign of nuclear activity, however. My source also mentioned that Japanese sensors picked up no radiation signatures.
This further confirms some of what Bill Gertz reported in the Washington Times this morning.