North Korea says that it has tested a hydrogen bomb. This seems unlikely, but it will be weeks before we know for sure. Most likely it was just another fission bomb test.
More interesting is what this says about relations between North Korea and China. Short answer: not so great.
The decision to detonate a bomb suggested a serious falling-out in the relationship between North Korea and China....Now, Chinese leaders are in a difficult position. They are under intense pressure to inflict harsh economic punishments on North Korea, but they worry that any resulting instability could seep back into their territory. They also face new questions about China’s efforts, over the past several months, to curry favor with Mr. Kim, whom many Chinese regard as a bizarre, bumbling figure.
China must also reckon with the prospect that actions by the North could galvanize countries like the United States, Japan and South Korea into strengthening military forces in the Pacific, just as China is seeking to assert its dominance in the region.
There's something a little hard to understand about China's continued sponsorship of North Korea. Historically it's easy enough to understand, but for the past couple of decades it's surely been nothing but a huge millstone around their necks. Are they really that worried about problems on the border with North Korea? Would they really lose that much face if they abandoned North Korea for good? And surely that would be more than made up for by the goodwill it would generate with the West.
I dunno. I get that questions of loyalty and fear of unrest aren't always entirely rational. Still, it's hard to see that China's alliance with North Korea buys it anything at all these days. If the DPRK imploded tomorrow, wouldn't they breathe the same sigh of relief as everyone else in the world?