New York Times: Here is a remarkable fact about global warming: It might be twice as bad right now were it not for a treaty negotiated by a conservative American president, for an entirely different purpose, based on motives no one has ever quite understood.
That treaty is known, in shorthand, as the Montreal Protocol. Its formal purpose is to save the ozone layer in the upper atmosphere, which protects the planet and its people from debilitating levels of cancer-causing ultraviolet radiation.
The negotiations...