Ah, sex education. I remember it like it was yesterday. It would have been 1987. Our entire year assembled in the school theatre. A beige, moustachioed, Open-University-looking chap stood alone on the stage with a slide projector. We’d never seen him before and never saw him again. He had been hired in especially for the occasion, I fancy, in much the same way and for much the same reason Russia uses the Wagner group to supply combat troops.