Boris Johnson was on his own. He had been self-isolating for a week since testing positive for coronavirus. His domestic staff left trays of food outside his apartment door.

Typically, the 55-year-old was bullish about life, even though the disease was at that moment working its way even deeper into his body. An old friend, Will Walden, sent him a text to ask how he was. "We’re going to beat it,” Johnson replied. Four days later, the British prime minister was lying in intensive care being given oxygen to help him breathe.

Now out of danger, Johnson on Thursday was allowed back onto the main ward at St. Thomas’ Hospital, where he had been admitted with a persistent cough and fever. But while his colleagues were relieved at the news, the question now being asked is how the leader of a Group of Seven country, one of the world’s biggest economies, was allowed to become so seriously ill when the nation needed him most.