Vincent Kessler / Reuters

The Brexit saga has now been going on for so long that, despite the daily twists and turns, it is starting to feel as though nothing ever changes. As one expert recently quipped, in the year 2192 the British prime minister might still make annual visits to Brussels “to ask for an extension of the Brexit deadline. No one remembers where this tradition originated, but every year it attracts many tourists from all over the world.”

And yet something consequential actually did happen on Tuesday: For the first time since the country opted to leave the European Union in the summer of 2016, a withdrawal agreement won a majority in the House of Commons. This is all the more remarkable because the deal proposed by Boris Johnson is very similar to the one Theresa May put forward earlier this year, only to see it go down in ignoble defeat at the hands of some of the same members of Parliament who now gave it their blessing.

The next weeks still hold a lot of uncertainty; from new elections to a no-deal Brexit, all options theoretically remain on the table. Nevertheless, it now looks likely that Johnson will take Britain out of both the EU and the single market that stands at its core.

How did he manage to do this after so many years treading water?

Pundits and politicians alike have mostly framed Brexit as a matter of public policy. During the decades of Britain’s membership in the European club, its political and economic system became closely intertwined with that of the Continent. And while the outcome of the 2016 referendum created a mandate for the country to leave the EU, it left a raft of important questions unanswered about the future nature of the country’s relationship with the Continent: On what terms would the United Kingdom trade with the rest of Europe? What rights would EU citizens in the U.K. enjoy? And what should happen to Northern Ireland?

For three agonizing years, May tried to find plausible answers to these questions. But though she did make some progress in squaring the circle, she failed to give either side of the debate a real reason to support her. Those who wanted to preserve a close relationship between Britain and the EU felt that May was harming the country’s economic future by proposing to leave the single market. Those who wanted to make a clean break with Europe felt that Britain would remain overly beholden to rules made in Brussels. Both had reason to fear that May’s deal left the country less influential than it was as a member of the EU, without giving it the freedom to chart its own path that might come with a more radical break.

The deal for which Johnson has now won a majority shares those shortcomings. It provides more details about how Northern Ireland might continue to enjoy frictionless trade with the Republic of Ireland without being cut off from the rest of the U.K. But it, too, raises the prospect that Britain will, in the future, either have to follow Brussels’s lead on key regulations or suffer from tariffs that would inflict serious damage to its economy. Seen from a public-policy perspective, it is therefore utterly baffling why a decisive number of MPs—most of them so-called hard Brexiteers—voted for it. The only plausible explanation is that Brexit was never really about public policy in the first place.

Britain’s fight about Brexit is best understood as a civil war over the country’s culture.

Remainers believe that important parts of contemporary Britain are in need of serious reform. But they also tend to be in tune with the beliefs of the country’s cultural elite, and to think that its core institutions are worth preserving. By and large, they trust the BBC, think highly of the country’s universities, and believe that Britain’s place in the world—as a medium-size power exerting its influence through multilateral institutions such as NATO and the United Nations—is appropriate.

Leavers, by contrast, feel that these institutions have come to be dominated by a left-liberal cultural establishment that looks down on them and sells the country short. They accuse the BBC of having a left-wing bias. They believe that universities serve to indoctrinate their children. And though they are confident that their country could manage on its own, they have grown convinced that most politicians are too timid to help it regain its past grandeur.

This explains why Brexiteers never trusted May. For May, who voted for Remain, Brexit was always a technical challenge of public policy that the cruel gods of politics had inexplicably forced her to solve in return for her spot in the limelight. If only she accomplished this devilishly difficult task, she believed, she could go on to be a good old-fashioned prime minister.

Johnson, however, has always understood that Brexit is as much a symbol as a cause. A lot of people voted for Brexit out of a desire to show an establishment they had come to loath who was really in charge; above and beyond negotiating an exit, pleasing them would require the leader to prove that (s)he is on the side of the angry people rather than on that of technocratic elites.

Now, Johnson is very much a product of the British establishment that has fallen out of favor. But like Jaroslaw Kaczynski in Poland and Donald Trump in the United States, he has made a name for himself in politics by assailing the pieties of left-liberal orthodoxy. And while the deal he presented to Parliament was little more than May’s hard-won package with copious lipstick smeared on top, the rhetoric he has employed since taking office has been radically different. By unabashedly leaning into populist language and loudly denouncing traditional institutions from Parliament to the Supreme Court, he has shown that he sees Brexit as the beginning, rather than the end, of Britain’s cultural revolution.

Johnson has remade himself—as well as the Conservatives, the oldest political party in the world—in the image of populism.

He depicts the country’s politics as being defined by a clash between two basic forces: On the one hand is an out-of-touch elite that is so beholden to its left-liberal values that it would gladly override the will of British voters. On the other hand are the pure people, who have voted for Brexit in a heroic attempt to put a stop to the elite’s domination of the country. Johnson’s core promise is to help the pure people triumph over the corrupt elite.

Ever since coming to office, Johnson has used this basic narrative to delegitimize any independent institution that clashes with him. Styling the Conservatives as the “party of the people,” he has attacked the legitimacy of the courts, the media, and even Parliament itself. As he said to loud laughs and a rousing round of applause at the Conservative Party Conference, “Voters have more say over [the British reality-television show] I’m a Celebrity than they do over this House of Commons.”

It is this populist side that has allowed Johnson to keep the loyalty of hard Brexiteers even as he has made more or less the same concessions that led them to denounce May as a traitor. What they want more than anything else is for Brexit to be a tool with which they can smash the existing establishment; by dressing up his relatively conciliatory stance toward Europe in the clothes of cultural revolution, Johnson has been able to assure them that the project of lambasting the elite will live on after they have signed off on his deal.

Once Brexit ceases to be the all-consuming topic of British politics, Johnson is likely to take the same approach to different policy areas: In tone, he will remain a strident populist. In substance, he is likely to pursue comparatively moderate policies.

A few key decisions he has made already point in that direction. After years of restrained government spending, he has substantially increased investment in a broad range of areas, from policing to education. And though he has at times used derogatory language about minority communities, he is taking steps to welcome more high-skilled immigrants to Britain: Reversing a rule set by his predecessor, for example, he is granting two-year work visas to students who complete an undergraduate degree in the country.

In a fragmented political system—and at a time when the Labour Party is headed by the most unpopular opposition leader in living memory—this recipe may just give Johnson a dominating position for the next decade. His populist style is allowing him to squeeze out the Brexit Party, consolidating support for himself on the right of British politics; his comparatively moderate policies, as well as his history as a popular mayor in highly diverse London, ensure that he does not inspire the same fear and mistrust among ethnic or religious minorities as far-right populists such as Trump often do.

Johnson may just be able to retain the support of the populist right while making real inroads with the country’s diverse middle class. If he plays his cards right, he will dominate British politics for much longer than pundits expect—and inspire imitators well beyond the shores of Brexit Britain.

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