The underlying theme of this three-part series, authoritatively helmed by Cambridge politics professor David Runciman, was an issue several times touched on in the opening speeches at COP26. Politics usually works to the short-term cycle of four- or five-year elections; expediency is all. How, then, do you budget for something like climate change, the progress of which cannot easily be stopped and which has practically infinite long-term consequences? As Runciman put it in one of his many pithy summings-up: “What’s the point of having a 50-year plan if you lose the next election?”