Great Britain

Opinion - The United Kingdom Has Voted. Will It Remain United?

Of all the agonizing twists and turns of British politics since the narrow vote on June 23, 2016, in favor of leaving the European Union, the landslide victory of Boris Johnson in Thursday’s election may be the most stunning. It also should have been the most predictable. After three and a half years of debilitating debate, the British had simply had enough and rallied to Mr. Johnson’s unvarnished slogan, “Get Brexit Done.” They are likely to get a very different Britain in the bargain.

The scale of the Conservative victory, and the extent of its conquests in traditional Labour strongholds, may not have been anticipated. But the bullish reaction from the markets, and, somewhat more counterintuitively, the celebration in Brussels, were further reflections of a widespread sense that “If it were done when ’tis done, then ’twere well it were done quickly.”

Brexit is now a fact, and that is the first and most concrete takeaway from the election. Without any viable opposition in his own Tory ranks, whose dissidents he had purged before the election and whose deputies all vowed to support him on Brexit, Mr. Johnson is likely to get his Brexit bill through Parliament within days or weeks, and Britain to formally leave the union by the end-of-January deadline. For many Britons and for many leaders of the Continent, ending the endless bickering and the threat of a chaotic deal-less Brexit was a source of great relief.

But that does not mean Brexit is “done,” or that it will be done quickly. It only opens the next, and arguably more difficult, stage of disentangling Britain from the vast and complex economic relationships that form the customs links and single market of the European Union, a task that is supposed to be done within a year but probably won’t be. Throughout the campaign, in which Mr. Johnson was successfully shielded from too much exposure to too many difficult questions, he gave little sense of how he would proceed.

That is only one of many areas in which Mr. Johnson has given little indication of how he intends to use the enormous political power the election handed him for the next five years. It is worth recalling that during most of the referendum campaign he was still the mayor of London, pondering whether he was for or against Brexit, and that most of his energies since were focused on getting into 10 Downing Street.

He eventually settled on a hard pro-Brexit stance, combining that with shameless populism; a smattering of lies; a way with words; and what turned out to be a winning strategy to capitalize on the weakness of Labour under its unpopular left-wing leader, Jeremy Corbyn. (“You voted to be Corbyn-neutral by Christmas,” was Mr. Johnson’s typical quip, playing off his pledge for Britain to be carbon-neutral by 2050.)

But the first wave of commentaries in the immediate aftermath of the election results were already wondering what new world was being ushered in. The survival of the “United” in United Kingdom itself was in question after a strong showing by the nationalist party in Scotland and its certain demand for a new referendum on independence, as well as the uncertain fate of Northern Ireland under Mr. Johnson’s Brexit plan.

Then there was the uncertainty over whether Mr. Johnson would or could live up to his pledges of enormous spending on the national health service, schools and the environment, pledges that helped him pry working-class voters away from Labour.

It is inevitable that Americans will search for parallels between Mr. Johnson and President Trump, and between the humiliation of Labour and the Democratic Party’s search for a standard-bearer. From the time he became prime minister, the disheveled, populist and often untruthful Mr. Johnson has often been compared to Mr. Trump, who has made no bones about his affinity for Mr. Johnson and was among the first to tweet congratulations on “his great WIN!” and to promise a “far bigger and more lucrative” trade deal than any Britain had with the European Union. In many ways, Mr. Johnson’s success in tapping into the discontent of working-class workers resembles Mr. Trump’s route to power.

And there are bound to be suggestions that Democrats should learn from the weaknesses of Mr. Corbyn’s Labour, which remained mired in left-wing promises of nationalizations and huge spending while failing to appreciate that its followers were becoming more nationalistic and socially conservative. Mr. Corbyn himself became entangled trying to deny the anti-Semitism in Labour’s anti-Israel stance, and his speech after the election typically blamed the media for the party’s loss.

There are lessons to be learned, no doubt, but it is also important to underscore the differences. Whatever his clownish quirks and failings, Mr. Johnson is a seasoned politician who knows and understands the workings of British politics and is familiar with the continent from which he is separating his country. That may be of little solace to liberal voters in Britain who see Brexit as a disaster and Mr. Johnson as an opportunist, but at least Mr. Johnson is not likely to succumb to the turnstile dysfunction or rule by tweet of Mr. Trump’s White House.

And while Mr. Corbyn’s dogmatic ideology did harm Labour’s chances, his unclear position on Brexit, which had strong support among workers, and his personal lack of popularity were probably a greater factor in his defeat than his socialist platform.

One certainty is that Britain faces an intense, broad and prolonged debate on its identity and its future. Whether Mr. Johnson can lead his country through the challenges that lie ahead is far from clear from his history or his record. But he is full of surprises, not least of which was Thursday’s victory. Let us hope that a newfound sense of responsibility is among them.