The Koreans have a long and lusty history of instransigence and national identity all of their own, with the national legends, scars and bruises to back it up. It does not need prompting from China to take a threatening posture.

Nor is there much resemblance at this point between what passes for Communism in North Korea and what passes for it in China. The two movements have diverged ideologically and pragmatically, until they scarcely resemble each other at all. They are not "brothers in arms against the Capitalist warmongerers." To the contrary; China has branded its own form of capitalism, a form very different from that seen in the West, and is on track to creat a regional economic hegemony. North Korea has done no such thing.

But we cannot quite escape this fact. China is the 800-lb gorilla in that part of the world, and without at least some commerce from China, North Korea will collapse. China does have influence.

China also plays a very long game. They are Machiavellian, but with the patience of Job.

What are their strategic goals? Economic regional domination is certainly one of them. Improving their standard of living is another. Securing resources and living space for their ever-expanding population is another.

They can't do those things if they are confined to their current patch of soil. Their population is up to 1.2 billion and still rising. The glaciers which feed their rivers are going away. Climate change is likely to produce some serious problems for China. Overpopulation already does.

The truth is that Taiwan and the Spratleys - which are, on the surface, the targets of their diplomatic and military intrigues - are irrelevant to their needs. Drops in the bucket. Yet they never cease to make noises as though these were the most important things in the universe.

Sun-Tsu would have got it. Distract the enemy; keep him from understanding your goals.

There are really only two options open to China for securing their long-range interests. One is to follow Japan's example and attempt to stitch together a pan-Pacific empire, with all the advantages that would accrue from controlling the Pacific. The downsides? The Pacific is already heavily populated, and the Pacific is a US lake. Admittedly, the US is overextended and has made some poor choices. It's now a debtor nation and in decline. Patience may yet deliver into their hands the Pacific.

But the real prize is Siberia.

In the race to the bottom, the Russians have a good head start over the US. They've already lost part of their empire. What remains is a poorly-glued conglomeration of ethnicities who have never been particularly happy about the Russian yoke. Russia is fragile. A good hard tap might send it spiraling down into civil war.

If a Russian civil war plays out right, Siberia could be up for grabs. Alliances with factions are possible, and so is the chance that the international community would welcome Chinese intervention to grab loose nukes. Nobody likes to contemplate a Russian civil war with loose nukes wandering the countryside. The result could be China squatting on Siberia and moving hundreds of millions in to colonize it.

Siberia has what China needs. Land, much of it quite fertile. A low population density. Minerals and petroleum largely left untapped by the Russians. It's perfect, if they can get their hands on it.

So they wait. Build up their economic and military strength. And keep us distracted, worried about things that do not matter in the least.

I do not think China controls North Korea. But I do not doubt their influence. The noise North Korea is making plays to China's strategic advantage by keeping us focused on unimportant things.