[tamu]

I see it in simpler terms - China has been uber-peeved at the US for exporting inflation to China. Japan is the strongest US ally in the region, has a bad history with China to begin with and has now begun QE in earnest (due to its negative current account). In concert, this crossed the line with TPTB in China, so it’s go time with all sorts of bluster out of their puppet Norks in an attempt to get the Japanese back in line.
The Japanese PM was in the States awhile back. I thought they were talking about securing NG shipments long term post Fukushima. Evidently there was a lot more being discussed!!

[expat_panama]

"China has been uber-peeved at the US for exporting inflation to China..."

That must be why America doesn't have any --kind of like all that 'exporting jobs to China' maybe?.