Mitford’s infinitely more humourless heirs – rather oddly, given what I imagine they’d think of her – can be found in the angrier fringes of the various new politics firms: the Kippers, the cybernats, the Corbynistas. They may be divided in their beliefs, but they are united by a mania for pigeonholing. We now have New, and non-New. All public statements, all things in the world, and most especially all people, must be deemed either for them or against them, and worshipped or demonised accordingly. There is no appeals procedure.