Because, you can actually watch Chinese air. Alex Tabarrok over on Marginal Revolution has the following dispatch about the new pollution poster child, the People’s Republic of China:

An hour and a half out of central Beijing, traveling through orchards of apples and pears and still the smog blankets the fields obscuring the view. Pollution like this I have never seen. And yet the intensity of the pollution makes me optimistic. Pollution in China isn’t like the demise of the snail darter or some wispy thing that might take a few weeks off your life if you live long enough. Pollution here irritates, it chokes and it kills young and old. Pollution like this people are willing to pay to avoid and as the economy grows the Chinese are willing to pay more and more. James Fallows, who is living in Beijing, suggests that pollution could be China’s Silver Lining, and ours. I read the piece before arriving but after being here a while it rings true.

If the world comes to realize which country it is that has the most work to do in environmental terms — and it isn’t U.S. — that is a silver lining.