Lefties, with one or two notable exceptions, are a sour, boot-faced lot. They are inevitably so because they are motivated by grievance and envy, neither of which is a sentiment guaranteed to put joy in one's heart. They seek offence where none is intended; they strive to suppress individuality of expression; they like to control others. Humour, whose main purpose throughout existence has been to deflate such priggish, pompous and sour attitudes, is therefore the enemy of militant Lefties, who wish to standardise attitudes and behaviour, and whose political project is to enforce and inflict as much control as possible over others.Quite. Though Cameron would present a more difficult target for the miserabilists if his jokes were any good. I am convinced enough now of his good humour. It's his political courage I doubt.