Efforts in Congress to pass a meaningful climate-change bill have ended for now. This is a big setback. The Capitol Hill approach to cap and trade had self-canceling aspects and was far from ideal, but it would at least have started to raise the price of carbon, which is something the world needs to do. A simple carbon tax would be much better, but if a semi-neutered cap and trade bill cannot pass, the chances of an explicit carbon tax must be smaller still.

Who is to blame? First the Republicans, for failing to take the problem seriously, and reflexively opposing any and all tax increases. Next the Democrats, for pretending that cap and trade was not a tax and trying to con the public. Obama, for choosing to stand aside. Not least, the IPCC and its penumbra, for eroding the credibility of climate science and weakening the consensus among voters that action is needed.

My new column for the FT goes into a bit more detail.

In all these political calculations, one fact looms large: voters are worried about climate change, but not enough to demand, or perhaps even tolerate, meaningful action. This is why the politicians acted as they did. Stronger leadership would have helped, no doubt. Still, you have to wonder why public opinion is failing of its own accord to demand action. The answer is not, I think, that voters on the whole are stupid - something many politicians believe rather too openly. In part, it is that climate science has trashed its own credibility.

Leading scientists have worked as activists rather than scholars, on the principle that the public needs to be scared and must not be troubled with complications. Uncertainties are suppressed, disagreements kept quiet, inconvenient truths set aside. The science is settled: that is all the public can handle.

The Intergovernmental Panel on Climate Change institutionalized the idea and the Climategate e-mails opened a window on the process. What was supposed to be a disinterested clearing-house for science to guide policy became, in part, a taxpayer-funded lobbying shop - and a notably incompetent one. The science was fitted to the case for action rather than the other way round. The public does not trust scientist-activists, and is right not to.

The easy part is mending the IPCC: new leadership, clearer mandate (no more campaigning: leave politics to politicians), and proper oversight. At the moment, getting to a constructive debate about tax policy--which takes in energy but which also goes broader--is harder to imagine.

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