Imagine, Mr Tsang, your two sons are toddlers once again. Imagine them wheezing and choking their way to a play date, as many did last week, (or perhaps to the doctor's, to see if they've yet succumbed to asthma). Imagine them as primary-school students, stuck inside their classrooms at play time because the air outside is too toxic to inhale (and little better inside). Imagine them now as young teenagers, gasping their way through a game of tennis or football. If your boys were younger, Mr Tsang, would you feel compelled to do something about the filth Hongkongers must inhale? Obviously, there is nothing the government can do about the effects of sandstorms and little it can do about pollution emanating from Pearl River Delta factories, but studies have found most of our muck is of our own making. What about that ban on idling motor engines - asked for by the public more than two years ago? What about exerting greater pressure on our power (and smog) generators to clean up their act? And what about addressing the harmful practices of our shipping and port operators? All these issues have been talked about ad nauseam but vested interests have prevented much action being taken. We realise that our health is of little importance to you, Mr Tsang, but, tell us, would you have sacrificed the well-being of your own sons when they were at their most vulnerable to benefit the friends of government?