LONDON—As a columnist, now-U.K. Prime Minister Boris Johnson was known for his rambling literary style, something he’s managed to top now with his well-publicized texting tone. This week, the public has seen messages from Johnson to vacuum mogul James Dyson from 2020 assuring him that he would “fix” a tax situation for the billionaire’s staff. Concerns were raised in and around the British government about the apparent ease with which anyone might text the prime minister directly for a favor. The U.K.’s most senior civil servant, Simon Case, reportedly advised Johnson to change his phone number. Apparently, he refused.
