Tom Holland
If the environmental policies of the United States and China seem inexplicable, a little game theory might shed light on the positions of the world's two biggest polluters.
US climate policy seems the epitome of double think. The administration has finally acknowledged the reality of global warming and conceded that human discharges of greenhouse gases are indeed to blame. But it still refuses to accept the need for a mandatory limit on emissions, arguing that such restrictions would damage the US economy.
Beijing, too, rejects the idea of capping its greenhouse gas emissions. Beijing says China is a poor country where emissions are relatively low on a per capita basis. It argues that most of the rise in greenhouse gas concentrations in the atmosphere is the result of past emissions from developed countries, and that to accept a ceiling on discharges would unfairly hinder the country's economic development.
Both of these stances are deeply flawed. Each rejects emission caps because of their supposed economic cost, but both ignore the far greater likely economic burden of failing to limit greenhouse gas emissions. According to last year's Stern report, the most authoritative study yet of the economics of climate change, doing nothing to check emissions will cost us between 5 and 20 per cent of global gross domestic product by the second half of the century. In contrast, stabilising emissions over the next 10 to 20 years will cost at most 3.5 per cent of world GDP.
Given that the projected benefits of emission caps so heavily outweigh the likely costs, it is hard to see why governments are still resisting the idea.