The obvious answer is because he won so many millions of votes — and, like Mr. Trump in 2016, he performed well in some places that the left usually carried. Alongside the evasiveness and clowning, Mr. Johnson has extraordinary charisma and a professional comic’s sense of timing. He is exceptionally clever, including emotionally: He projects the subtle suggestion of underlying personal pain, an appeal for understanding, even love, that so many authoritarian leaders have shared. And he understands the rhythms of political life. He exploited the fierce emotions caused by the referendum to leave the European Union, and then in 2019 he won the passionate support of voters who found conventional politicians pious, dreary and remote.
But the more he embodied a cult leader, the more the Conservatives allowed him to distort traditional norms on which Britain, like so many older democracies, has relied. Throughout the 20th century, political competition in most major democratic countries depended upon big, vaguely ideas-based political parties. They were always riven by internal splits, and they were baggy coalitions of interest, but there was essential agreement about the size of the state, taxes, liberty and economics.
In younger democracies, political parties have more often been like machines for leaders. Populism, or the cult of the angry leader, has dressed itself in conventional party clothing in countries such as Zimbabwe, Argentina or India.
Now, something similar is arriving in the West. Mr. Johnson is not, and never was, “Britain Trump” — he is much more liberal, a believer in the virtues of some immigration and a consistent believer in the reality of man-made global warming. He is, most of the time, less menacing toward his opponents. He prefers to joke rather than to goad. But he has been like Mr. Trump in his readiness to bend rules, and bend the truth, to gain and hold power; and like Mr. Trump in his almost mystical connection with voters who had previously thought themselves shunned by the political establishment.
Democracies with leaders who possess a cult of personality have been spreading around the world, whether in India with Narendra Modi, Hungary with Viktor Orbán or Brazil with Jair Bolsonaro. They depend on a more passionate identification between voters and the single leader, on whom hope, prosperity and security depend. It produces a more overheated political atmosphere — at times more the mood of an evangelical chapel than of a town-hall meeting.
The great weakness is that when the leader fails, or is exposed as fallible, everything fails. Britain is being mocked from Moscow to Washington; across the European Union, cartoonists, satirists and commentators delight in ridiculing Mr. Johnson.
Conservatives now ask themselves who they really are. Socially liberal as Mr. Johnson was when he was London’s mayor — or socially conservative like many of their new working class voters? Defenders of elite bankers and big corporations — many top Conservatives come from business — or champions of their new, poorer, post-Brexit Tory voters, angry about economic unfairness?