A recent opinion poll suggests that 70 per cent of people in the UK are worried about air pollution and half want the state to do more. The British government does nothing.

The main problem are highly polluting diesel vehicles. Air pollution will gradually fall as the oldest, most polluting vehicles are replaced. Yet the courts have ruled that the government must act now, regardless of cost. Air pollution campaigners say ministers have instead taken the cynical decision that it is cheaper to continue breaking the law.

There is no doubt that air pollution is bad for us. The damage can start before a child is born, restricting growth and brain development in the uterus, with lifelong effects. Children exposed to high levels of air pollution have lower lung function and have far more respiratory infections.

In adults, the result is more likely to be cancer, cardiovascular disease, diabetes or obesity. A US study that followed half a million people for 15 years found that those exposed to greater amounts of air pollution were more likely to die early, although it is difficult to establish what role air pollution plays in individual cases.

I long ago gave up my British driving lucence. The traffic is so dense and the driving so bad that if we can’t reach our destination by public transport we don’t go at all. But that doesn’t bear upon pollution except in so far as there are just too many vehicles on the road, pouring forth huge volumes of particulates.

Even if you don’t drive you can get seriouly ill living on a busy street or daily walking along it. Electric cars are a help (although the electricity still has to be generated), and a higher gas tax is badly needed, especially in America. The government debt is humungous, so why not at last tax people more for polluting and thus lower the debt a bit. Call it a pollution tax. This is suggested tongue in cheek. It’s the political version of suicide. People prefer to die, one assumes, than pay more tax.