Imagine a disease spreading across the globe, killing mostly middle-aged people or leaving them chronically disabled. Then one day researchers come up with a drug that can prevent some of the disease's nastier effects. You would think the world's ageing public would be eternally grateful.

The disease does exist. It is called tobacco addiction. The drug too is real and in animal tests has prevented lung damage that leads to emphysema. But the inventors have received no bouquets. Prevailing medical opinion seems to be that the drug is a mere sideshow, distracting smokers from the task of quitting. Another experimental drug, which could protect smokers against cancer, is also viewed with suspicion because it could give smokers an excuse not to quit.

On the face of it these responses make sense. It is ingrained in society that smokers have only themselves to blame and their salvation lies in a simple act of will. If they will not quit smoking, they cannot expect help from anyone else.

But this logic is flawed. Check a survey of smokers and you find two-thirds want to give up and one-third will have tried in the previous year. Yet, even with nicotine gum, patches and drugs to ease the ordeal, the quit rate is still under 10 per cent. In the UK, the proportion of people who smoke has not fallen in a decade. Tobacco has a powerful grip, and many smokers are caught in a trap they cannot escape: they have a disease like any other and deserve the chance to reduce the harm it does to them.

This reasoning is hard for many to swallow. It certainly leaves governments and anti-smoking groups in a bind. They are happy to pay lip service to methods for reducing harm of which there are a growing number—but they are slow to create policies based upon them. European Union countries, for example, took years to even consider regulating the dangerous additives in cigarettes.

One fear is that methods for reducing harm will dilute the message that tobacco kills—especially when given to youngsters. But that message won't change. In the present case, even if both drugs turn out to work in human trials, they would not protect against all the deadly side effects of smoking. And the drugs do not have to be free to all. They could be available only on prescription for people who doctors believe genuinely cannot give up.

There are things that no drug aimed at harm reduction will ever be able to do. It will not cut passive smoking or stop tobacco companies persuading millions of teenagers to light up. For these reasons all other ways to counter smoking must continue, from banning tobacco advertising to raising tobacco taxes. But it would be a mistake to ignore the harm reduction measures. For those who are not convinced, forget smokers for a moment. Preventive drugs could also help non-smokers, especially those working long hours, as, say, musicians and bar staff in smoky rooms. Should we deny them too?