Neil Hall / Reuters

The morning after Britain voted to leave the European Union, the Remain campaign and the overwhelmingly young, urban liberals who championed its cause, awoke to the reality of bitter, unexpected defeat. Tammy Palmer, an activist who campaigned against Brexit, cried all the way to work. “By the time I got off the tube, I was like, right, screw it, I’m going to find an army, and I’m going to lead that army, and [Brexit] is not going to happen,” she said. People poured out onto the streets to protest the outcome, to march for Europe. Then, they started organizing. Emails with subject lines like “#GenerationFucked #SaveLondon #SaveBritain” circulated among young activists and writers, sketching out possible plans for action.

The days following Donald Trump’s surprise victory in the U.S. presidential election have been marked by a similar public outcry among those who opposed it. The demonstrations in front of Trump Tower, and parallel protests in Miami, Atlanta, Portland, Iowa, Raleigh, and elsewhere, are manifestations of a similar sense of betrayal, anger, and confusion to what shook Britain’s young, globally minded voters in late June. In the United States, more than 4 million people have signed a petition imploring the electoral college to elect Hillary Clinton instead of Donald Trump on December 19. Similarly, in Britain, many hope the government might block Brexit, despite the fact that 17.4 million citizens—52 percent of voters—voted for it. There’s a certain futility in both efforts, and danger in the anti-democratic sentiments they evoke.

Now, anti-Brexit campaigners look across the Atlantic with trepidation. Five months past the protest stage, they’re still deciding how to channel their outrage into political action, fighting internal division and burnout, and realizing now—unlike during the lead-up to the referendum—that they must begin making inroads with the opposing side.

Though the vote for Trump and the vote to leave the EU concerned drastically different issues, they were animated by the same dynamics: younger, urban, educated, affluent voters tended to opt for open borders, and to preserve the liberal status quo, while rural, older voters in places that have not reaped the benefits of globalization—the American Rust Belt, and the north and east of England—tended to swing the opposite way.

Josh Glancy, a British correspondent in New York, described the eerie parallels between the referendum vote and the U.S. presidential election. “Because I’ve been through Brexit, I kept telling people in Brooklyn to prepare, but no one really committed to the possibility, and that's why it hurts so much.” Nigel Farage, the UK Independence Party leader, campaigned avidly for Brexit, spreading misinformation about the benefits of leaving the EU. He has openly supported Trump’s campaign, traveling to the Republican National Convention, stumping for Trump, and, more recently, posing with him before the gilded doors of Trump Tower.

“When we all woke up this week, it felt like the 24th of June”—the morning after Brexit— “all over again. We were all mourning again,” Palmer said. She hasn’t spoken to her family members, who voted to leave the EU and live outside London, since the vote, and is trying to build a political future. In 2020, she hopes to stand for election as a member of parliament for the Liberal Democrats. She’s helping with grassroots outreach efforts, reaching out to Leave voters and young 16 and 17-year-olds who will soon be eligible to vote.

“Be tactical. Pick your supporters, pick the politicians who'll give you some information quietly, and find out what you need to do to influence people,” Palmer said. While the initial anti-Brexit marches brought tens of thousands of people to the streets, attendance at subsequent ones in less-united areas was paltry. “There has to be a point to a protest march, otherwise you look stupid. You look like a sore loser. They're great initially to rouse people, to get people angry,” Palmer said. “But if you're trying to use it for momentum, it can actually go the other way.”

Indeed, the biggest victory so far against Brexit arose not from the streets but from the high court, which in early November ruled in favor of Gina Miller, a British businesswoman who petitioned the court to rule on whether parliament must vote on triggering Article 50 of the Lisbon Treaty, which will initiate Britain’s departure from the EU. “A hundred thousand people marching on parliament would not have had 1 percent of the impact that she’s had,” Glancy said. Police have warned Miller to stay inside and avoid public spaces over concern for her safety—she has received death and rape threats on social media, and has been described as a “foreign-born immigrant” working against British democracy (Miller was born in British Guyana). Especially after the politically motivated murder of Labour MP Jo Cox a week prior to the referendum, the threats against Miller are not being taken lightly.

“If the Labour party sees a route back to success by trying to block the will of the people, they’re really on a road to nowhere—it’ll make them look extremely out of touch with their voters, and harm their electoral chances for the future,” said Matthew Elliott, chief executive of Vote Leave, who pointed out that similar disaffection was at play in the U.S. election. “They’ve got to recognize a big part of the leave vote were center-left, Labour party, blue-collar workers. The leave side was a 25-year effort to get the referendum, and then to pass it. … If people on the remain side think they can overturn this overnight, they’re mistaken.”

James Kingston, a young Conservative activist, described the situation in Britain as one of “classic post-revolutionary ferment,” with infighting and competition among opposition groups, disputes over branding, and “lots of disagreement on tactical, strategic avenues forward. People don’t know whether to reject the referendum results or argue over the terms [of Brexit].”

The disarray in Britain should be taken as a warning for the Democratic party in the United States. In the U.K., both the Labour Party and the Liberal Democrats have “failed to develop a coherent anti-Brexit political movement because that would have to include bond traders, left-wing activists, and union members,” as Will Davies, a political economist at Goldsmiths, University of London, described the crisis. “The opposition hasn’t congealed into a stable set of voices,” he added. In the United States, Hillary Clinton’s loss has already left the Democratic party deeply fractured, searching for new leadership. In both cases, that’s partly because there is uncertainty about what they should mobilize against—a leaked government memo suggests there is no plan for Brexit, and the Republican administration-in-waiting appears already to be in turmoil, having failed to move past some of the uglier racial elements of the campaign, and with many of its policies still opaque.

And in both cases, there remains the problem of adjusting to a new and uncertain reality. “This is a longer-term program. None of us knows how Brexit is going to work out. None of us knows how Trump’s presidency is going to work out,” said Alice Fermor-Hesketh, a member of the Labour party who now runs an initiative called Common Ground, which reaches out to towns that voted decisively to leave the EU. While she has continued her activism since the referendum, others seem exhausted by the sheer volume of work to be done. “Activism is quite new to us. We're just not a generation that felt the need to be active,” Fermor-Hesketh said.

Making progress for their agenda, several young activists quietly said, will likely mean moving away from some of the language that may have driven voters to the other side, reckoning with the repudiation of their approach, and figuring out what democracy really means. “People have this instinct to move very quickly, to start organizing protests,” one 20-something lawyer and activist said. The answer, he said, is to adjust to the slower, deliberate pace of campaign politics. “We need to be looking at the mid-term. It’s going to take five years, ten years to repair the cultural issues, the democratic issues. There just needs to be some time when the center and the left do some introspection, and maybe start wiping away this quite trendy culture that produced stuff like safe spaces,” he said. He was referring to a “general unwillingness amongst some liberals to really engage and take seriously views that challenge their own.” In doing so, people “feel they legitimize the ‘evil’ lurking behind anti-immigration arguments and betray what it is to be liberal, democratic.”

But the virulent bigotry and racism that emerged around the Leave campaign in Britain has made it difficult for those on the losing side to try to understand the motivations of some groups that supported Brexit. In the United States, Trump’s campaign framed its battle against the left in part as a fight against political correctness, seemingly pardoning the reintroduction of racist and sexist expression into American politics. Protests against Trump’s victory have already resulted in violent clashes, and incidents of harassment and intimidation of minorities skyrocketed since the vote. At the same time, both Remain and Clinton voters have no choice but to contend with their opposition.

“There's a certain arrogance among people like myself. I assumed people would never be stupid enough to do this,” Palmer said. “You hear this ‘liberal elite’ narrative, and liberalism has become a dirty word. We've brought some of that on ourselves—we've positioned ourselves as better than you—but actually that's nonsense. We are really trying to reach out to people, not to judge them, not to patronize them. The whole of this country isn’t racist, thank God. Most people don’t think that way.” In an interview with Politico, London Mayor Sadiq Khan echoed this sentiment.

The Remain campaign, or “Stronger In,” bore obvious similarities to the Clinton campaign, with its “Stronger Together” slogan, as one senior Labour party figure noted. “If in any way it looks like you're sneering at the people who voted for him, then you've lost,” he said, referring to Trump. “You've got to draw a line between the racism and misogyny of the candidate, and the reasons why quite a lot of people who you wanted on your side voted for him. … You've got to combat the populist right with some form of populism on the left, and you've got to change the cultural look and feel on the left.” Trump and Nigel Farage’s opponents may have scoffed at their baseball caps and Union Jack socks, but they became strong symbols of voter identification.

But there will be an opening for the opposition on both sides of the Atlantic if Trump and Farage fail to deliver on their populist promises. “The Leave vote preyed on vulnerable people. They’re going to start taking their benefits away—they're already in low-paying jobs, and they won’t have jobs if [Brexit] goes through,” Palmer said. Farage promised the British National Health Service would receive £350 million in funding from diverted EU funds, a groundless claim that he disowned the day after the vote. The Leave campaign also promised immigration limits that, it said, would allow the working class to “take back control” of their communities and jobs, but in reality those migration curbs, if they ever materialize, will be a long time coming. Trump promised to revive coal country, telling miners, “Get ready because you’re going to be working your asses off,” but neither he nor anyone else has any idea how to pull off such a miracle.

Palmer’s family voted to leave the EU because of concerns over immigration, “and I really struggle with that, because they brought me up and I'm not like that. I'm trying to understand what happened, what made them change,” Palmer said. “I still don’t know at this moment quite how we unite. ... Wherever I go, I think, ‘Are you one of us, or are you not?’ And that’s a difficult way to live.”

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