Has Boris lost the plot?

When the facts change, I change my mind. What do you do sir? That defence of the political u-turn was purportedly uttered by the great economist John Maynard Keynes and is recognised as the classic intellectually respectable case for abandoning a stance in favour of an opposite one. It is certainly the best defence available to Boris Johnson over his apparent volte face on mask-wearing with the new announcement that masks will be compulsory in shops from next week. World Health Organisation advice has warmed up on the protective value of masks over recent weeks and the experience of several other countries appears to bear out their usefulness.

On the other hand, when the stance a statesman first takes immediately appears to fail the test of common sense and then he later abandons it, an ebbing away of authority is likely to ensue. And when the new stance also appears to contradict other recently announced policies, voters might even conclude that a certain amount of losing of the plot has taken place.