More than that, a false hope of salvation can be actively harmful. If you persist in believing that catastrophe can be averted, you commit yourself to tackling a problem so immense that it needs to be everyone’s overriding priority forever. One result, weirdly, is a kind of complacency: by voting for green candidates, riding a bicycle to work, avoiding air travel, you might feel that you’ve done everything you can for the only thing worth doing. Whereas, if you accept the reality that the planet will soon overheat to the point of threatening civilization, there’s a whole lot more you should be doing.

Our resources aren’t infinite. Even if we invest much of them in a longest-shot gamble, reducing carbon emissions in the hope that it will save us, it’s unwise to invest all of them. Every billion dollars spent on high-speed trains, which may or may not be suitable for North America, is a billion not banked for disaster preparedness, reparations to inundated countries, or future humanitarian relief. Every renewable-energy mega-project that destroys a living ecosystem—the “green” energy development now occurring in Kenya’s national parks, the giant hydroelectric projects in Brazil, the construction of solar farms in open spaces, rather than in settled areas—erodes the resilience of a natural world already fighting for its life. Soil and water depletion, overuse of pesticides, the devastation of world fisheries—collective will is needed for these problems, too, and, unlike the problem of carbon, they’re within our power to solve. As a bonus, many low-tech conservation actions (restoring forests, preserving grasslands, eating less meat) can reduce our carbon footprint as effectively as massive industrial changes.