Sir Keir Starmer’s pessimism cheered the Prime Minister up. At last Boris Johnson could do what he does best, namely place himself at the head of the forces of optimism.

The PM is the Candide of British politics. While morose and conscientious scientists present mounting evidence that the pandemic is getting worse, Johnson holds out hope that we may yet find ourselves living in the best of all possible worlds.

Sir Keir demanded to know why Johnson had abandoned “the science” and “why the numbers are all heading in the wrong direction”?

Johnson retorted that the numbers in Cornwall are far better than the numbers in Liverpool, so it would be ridiculous to go for a nationwide “circuit breaker” lockdown, as advocated by Sir Keir, especially as Sir Keir keeps changing his mind.

The Leader of the Opposition proceeded to announce that the PM is “behind the curve” and “someone who’s been an opportunist all his life”.

Sir Keir added that he himself, on the other hand, has “genuinely concluded a circuit breaker is in the national interest”.

In other words, Sir Keir is a stern upholder of the truth while Johnson is a liar who will say absolutely anything in order to gain some temporary advantage over an opponent.

The problem with this accusation is not that Johnson is regarded as a pillar of moral rectitude, but that the British public thinks all politicians are liars will say absolutely anything in order to gain some temporary advantage over an opponent.

“They’re all the same,” as the man in the pub used to put it, in the days when he was allowed to go there.

Johnson proceeded to turn Sir Keir’s charge against Labour: “opportunism is I’m afraid the name of the game for the party opposite.”

There is, the PM urged, a better way: “Let’s work together…to keep kids in school…keep our economy going.”

The sunlit uplands are almost within sight. We can together make a better world. The doomsters and the gloomsters will, as he promised on another occasion, loose their shirts.

Sir Keir had become spokesman for the doomsters: “I can’t think of a single scientist who backs him.” Indeed, the Leader of the Opposition went on, according to The Daily Telegraph there is an 80 per cent chance the PM will back a circuit breaker in the next two weeks.

Johnson accused the Opposition of seeing this “as a good crisis for the Labour Party”, opportunism in other words, and added that while he ruled “out nothing of course in combatting the virus”, he was “going to do it with the local, the regional approach”.

The PM today sounded liberated, free at last to harness the power of wishful thinking, and defy the grim official wisdom for which Sir Keir has become chief advocate.