Should we ban cigarettes?

At the urging of his wife, Michelle Obama, the president first resolved to stop smoking in 2006, and has used nicotine replacement therapy to help him. If it took Obama, a man strong-willed enough to aspire to and achieve the US presidency, five years to kick the habit, it is not surprising that hundreds of millions of smokers find themselves unable to quit.

Although smoking has fallen sharply in the US, from about 40 percent of the population in 1970 to only 20 percent today, the proportion of smokers stopped dropping around 2004.