“These today are proud in power/And lord it in their little hour,” wrote A. E. Housman in A Shropshire Lad. On Thursday that county delivered a sharp reality check to Boris Johnson, proud in power since 2019, but now perhaps beginning to recognise the littleness of his hour. Whether or not it can be extended is the question that currently preoccupies the country, political commentators, the Conservative Party and, presumably, the Prime Minister himself.