Boris Johnson divides Britons in a way few other politicians manage. To his dwindling group of supporters, he is the hero who Got Brexit Done; to his detractors, he is a villain, edging the country towards a dark place. He is, according to Alastair Campbell, Britain’s ‘accidental fascist’. But if you stand back from the Westminster hurly-burly you can see Boris for what he is: a carefully constructed empty space onto which Britons have, over the years, been invited to project their hopes and fears; one whose purpose has been to further the personal ambition for power of the very...