... the 2008-9 plunge in world trade was one for the record books. What it mainly reflected was the fact that modern trade is dominated by sales of durable manufactured goods -- and in the face of severe financial crisis and its attendant uncertainty, both consumers and corporations postponed purchases of anything that wasn't needed immediately. How did this reduce the U.S. trade deficit? Imports of goods like automobiles collapsed; so did some U.S. exports; but because we came into the crisis importing much more than we exported, the net effect was a smaller trade gap.

But with the financial crisis abating, this process is going into reverse. Last week's U.S. trade report showed a sharp increase in the trade deficit between August and September. And there will be many more reports along those lines.

So picture this: month after month of headlines juxtaposing soaring U.S. trade deficits and Chinese trade surpluses with the suffering of unemployed American workers. If I were the Chinese government, I'd be really worried about that prospect.

Unfortunately, the Chinese don't seem to get it: rather than face up to the need to change their currency policy, they've taken to lecturing the United States, telling us to raise interest rates and curb fiscal deficits -- that is, to make our unemployment problem even worse.

And I'm not sure the Obama administration gets it, either. The administration's statements on Chinese currency policy seem pro forma, lacking any sense of urgency.

That needs to change. I don't begrudge Mr. Obama the banquets and the photo ops; they're part of his job. But behind the scenes he better be warning the Chinese that they're playing a dangerous game.