If you are going to give gongs for public service, I guess a three-times elected London mayor ought to be a candidate. True, it is hard to see what particular achievements have earned Sadiq Khan his knighthood. Violent crime has risen inexorably on his watch, while his efforts to clean up London’s air have been clumsy at best, making life next-to-impossible for low-wage shift workers in outer London who really don’t have any option but to commute to work in their 20 year-old cars.