So says Peter Huber:
We no longer control the demand for carbon, either. The 5 billion poor—the other 80 percent—are already the main problem, not us. Collectively, they emit 20 percent more greenhouse gas than we do. We burn a lot more carbon individually, but they have a lot more children. Their fecundity has eclipsed our gluttony, and the gap is now widening fast. China, not the United States, is now the planet’s largest emitter. Brazil, India, Indonesia, South Africa, and others are in hot pursuit. And these countries have all made it clear that they aren’t interested in spending what money they have on low-carb diets. ...
The grand theory for how the developed world can unilaterally save the planet seems to run like this. We buy time for the planet by rapidly slashing our own emissions. We do so by developing carbon-free alternatives even cheaper than carbon. The rest of the world will then quickly adopt these alternatives, leaving most of its trillion barrels of oil and trillion tons of coal safely buried, most of the rain forests standing, and most of the planet’s carbon-rich soil undisturbed. From end to end, however, this vision strains credulity.
His argument is simple: even if we (in the developed world) cut our carbon consumption markedly, the reduced demand will lower the price. Energy-starved developing economies will then take advantage of the lower price by ramping up their consumption by at least as much, and the net effect on emissions will be nil. We can't prevent them from doing this, nor we can afford to simply buy them off, because their sheer numbers are too great. In other words, we simply can't get past the economics of this even if we (in the developed world) were willing to sacrifice quite a lot to reduce emissions.
What can be done? Huber suggests that we cease spending time and money trying to hold back the inevitable tide. Instead we should invest in sequestering the carbon and sinking it back into the ground. This is best done, in Huber's mind, by investing in reforestation and other land use reform. In other words, Huber suggests taking better advantage of the earth's built-in stabilizers.
Would this be sufficient? Even Huber doesn't seem fully convinced. But there are reasons to think that the probability of sequestering working is greater than the probability of getting a bunch of treaties signed, ratified, and enforced. And sequestering comes with the added benefit of encouraging poor countries to grow out of poverty, rather than forcing them to stay poor.
For a different take, proposed by a Republican Congressman and member of the Pigou Club, see this letter.