In Westminster and Washington, relations between the government and journalists are at their lowest ebb. Routine lines of communication have been severed as political leaders use the electronic media to get their message out directly, bypassing the traditional mediators in print and on the airwaves.

In Whitehall the stand-off flared into an unprecedentedly ugly incident in the foyer behind the shiny black door of

No 10 Downing Street last week. First a security guard divided accredited correspondents into separate groups on either side of a carpet. Next Boris Johnson’s communications director, Lee Cain, himself a former reporter on The Sun and The Mail on Sunday, gave the order: “Those invited to the briefing can stay — everyone else, I’m afraid, will have to leave.”

After