The McCullough effect was discovered by a psychologist in Canada in 1965, and explained by Tom Scott in a video on YouTube. It involves staring at a coloured image (shown).

Only, they’re not black and white to most of us. In a series of images shared by economist Lionel Page, coloured lines, grids, and dots were placed on top of colourless pictures.

In a new paper, Iran: Red Lines and Grey Areas, just released by the Royal United Services Institute (RUSI), my colleague Hugh Chalmers and I argue that, despite Netanyahu’s loquaciousness on ...