Editorial: Science, economics and even the Holy See have failed to persuade the U.S. Congress to tackle climate change. Now, perhaps an even more powerful influence may come to bear: the determination not to be outdone by China.
On Friday, the world's largest emitter of greenhouse gases announced it will begin a national cap-and-trade program in 2017. It will limit total emissions and let individual emitters, including power, steel, chemicals and other industrial producers, trade emissions allowances --...