I flew into Britain on June 23, the day of the Brexit referendum, or “Independence Day” as the country’s most popular tabloid, and champion of leaving the European Union, put it. The next morning, results showed that London, Scotland, and Northern Ireland had voted to stay in the EU. But they were outweighed by a decisive vote to leave from the rest of the United Kingdom. It was a revolt of Welsh villages, northern English cities, and southern country towns.

As I walked the cobblestone streets of Durham, a cathedral city in the northeast of England where I grew up, it didn’t feel like Britain had won its freedom. The mood was nothing like America’s Fourth of July. There were no hot dogs being eaten, or fireworks rippling through the sky. “Independence Day” felt more like the aliens had just landed. Within hours, the pound lost 10 percent of its value. Business confidence plummeted. The country faced disunion. Nationalists in Scotland claimed that Scotland’s vote to “Remain” justified another referendum on Scottish independence.

The mood was anxious, melancholy, funereal. The British seemed to have disavowed their traditional pragmatism, and the joyous multicultural atmosphere of the 2012 London Olympics, and embraced something darker and more irrational. Remain supporters were shell-shocked, especially young people who saw their future living and working in the European Union suddenly ripped away. Even many Brexiters wondered what on earth they had done.

After a week of the Brexit blues, I flew to Finland. Sipping coffee and bathing in the endless summer light on Helsinki’s handsome Esplanade, I talked to Finns who were in disbelief at Britain’s decision, and fearful for the future. As a member of both the EU and the euro currency, Finland has much to lose from the collapse of the European project. But the threat to Finland’s place in Europe lay not just with the distant political earthquake in Britain. Finland faces its own populist revival—and the people leading it are already in the government.

In the early 2000s, the nationalist Finns Party received just over 1 percent of the vote, but in the 2015 elections, it won almost 18 percent, became the second-largest party in the Finnish Parliament, and entered a coalition government along with moderate parties. Brexit could pave the way for Fixit. The Finns Party suggested a referendum on leaving the European Union after the next Finnish elections in 2019. A recent poll found that a majority of Finns would vote to stay, but 44 percent felt that Finland would prosper more outside the EU.

The Trumpist International

The Brexit vote and the emergence of the Finns Party are both examples of the rise of Trumpism, a brew of nationalist, populist, anti-establishment, anti-“expert,” anti-globalist, protectionist, “us versus them,” and most of all, anti-immigrant sentiment. Nativist and anti-immigrant parties have arisen across Europe, including the National Front in France, the Party for Freedom in the Netherlands, the Jobbik party in Hungary, the Danish People’s Party, the Sweden Democrats, and the Progress Party in Norway.

Trumpism existed long before Donald Trump ever strode across the political stage, promising national greatness, as well as steaks, water, and wine. The American businessman rode a wave that has been building across America and the West for decades. Trump embraced and shaped the mood so profoundly that it’s possible to brand the movement with his name. Trumpists in the United States, Britain, Finland, and elsewhere, vary a great deal, reflecting different cultures and political situations. But they all draw on a common wellspring of grievances, and espouse parallel hopes, fears, and solutions.

The driving forces behind the rise of Trumpists are similar: the negative effects of globalization, economic anxiety, stagnant median wages, the fracturing of states in Syria, Libya, and elsewhere, and the resulting refugee flows. This is shaded by local circumstances. For example, Finland is a tolerant society, and in many respects the envy of the progressive world, with its highly rated health and education systems. But the Finnish economy has never recovered from the 2008 economic crisis. The decline of Nokia, once one of the country’s biggest companies, was a body blow. And Finland has suffered from the recession in neighboring Russia. Many Finns feel left behind or left out.

The Trumpists are often quite left-wing on the issue of the welfare state, and support a social safety net for “trueborn” citizens and “deserving” workers—but not for refugees or immigrants. The Finns Party backs the Finnish welfare model. Trump himself has promised to safeguard Social Security: “All these other people [in the GOP primary] want to cut the hell out of it. I’m not going to cut it at all.”

The glue that binds Trumpism together is anti-immigrant sentiment and fear of the “other.” In the United States, Trump’s supporters are defined by economic nationalism and skepticism toward immigrants. For example, one poll from last September found that 63 percent of Trumpists favored revoking birthright citizenship (compared to 51 percent in the overall GOP electorate). And 66 percent of Trump supporters claimed that U.S. President Barack Obama is a Muslim—12 points higher than the overall GOP figure.

Concern about immigration was probably a decisive factor in the Brexit vote. A study from 2015 found that of British people who wanted to stay in the EU, only one in five saw immigration as bad for the economy. For British people who sought to leave, the figure was almost seven in ten. Nigel Farage, the head of the U.K. Independence Party, and a prominent advocate of Brexit, spoke the language of Trumpism. One of Farage’s Brexit posters showed an apparent incoming horde of foreign and mostly non-white immigrants with the slogan “Breaking Point.” Similarly, the Finns Party has pledged to reduce the number of refugees, oppose multiculturalism, and teach national pride in schools. The Finnish populists described Roma immigrants as “criminals,” echoing Trump’s description of Mexican immigrants as “bringing drugs. They’re bringing crime. They’re rapists.” Whereas Trump proposed a ban on Muslims entering the United States, the Finns Party sought to prioritize asylum for Christians over other religious groups.

The Trumpist style is similar: a down-to-earth brand of everyman joviality, and a cavalcade of one-line zingers directed at the elites. The populists sometimes revel in anti-intellectualism. In Britain, the majority of economists and almost all international authorities, including the head of the International Monetary Fund, Obama, and leaders of virtually every British ally, warned about the potentially disastrous consequences of a Brexit. But Michael Gove, a Conservative Party MP and Leave proponent, retorted: “people in this country have had enough of experts.”

Trumpists often embrace each other as populist fellow travelers. In 2011, the head of the Finns Party was the star turn at a U.K. Independence Party conference. Trump himself was delighted by the Brexit vote: “People are angry, all over the world.”

Darker forces loom at the edges of the Trumpist movements. In the week after the Brexit vote, reported hate crimes in Britain increased five-fold. Meanwhile in Finland, a small group of Finns calling themselves the “Soldiers of Odin” have donned black jackets and started patrolling the streets to safeguard Finns from “Islamist intruders.” One Finns Party member and local politician in Helsinki suggested that African men who come to Finland and then have three children should be forcibly sterilized: “which would more effectively restrain their onslaught to our country in order to earn a better standard of living by fucking.”

The Global Fight

There is a Western or even worldwide contest between Trumpists and progressives. The stakes are extraordinarily high. The global liberal order, an open and rule-based system based on free trade and international institutions like the IMF, the World Bank, the UN and the EU, has helped to deliver peace and security since 1945. But Trumpists want to bring this order crashing down.

July 1 was a somber day in Britain, not just because of the Brexit vote, but also because it was the centenary of the Battle of the Somme in World War I, when British troops were ordered to march across no man’s land into a hail of German machine gun fire, and 57,000 British soldiers were killed or injured on the first day alone. The Somme is a reminder of life in Europe before the liberal order.

Trump’s victory in the U.S. elections in November wouldn’t just represent a sea change in American politics; it would also encourage Trumpists everywhere. Nativists throughout the West would believe they have captured the zeitgeist, and that this is their moment. Trump’s triumph would provide a model to emulate. And if President Trump managed to sharply reduce U.S. immigration, it could trigger similar responses in other countries in a populist domino effect.

The rise of Trumpism is a defining challenge for progressives. The left is used to debating the right on the traditional conservative triad of a strong military, social conservatism, and tax cuts. But Trumpism represents new and politically dangerous terrain. It taps into nationalism, the most powerful motivating force in modern political history. It offers a potent emotional appeal to communities that feel ignored. Whereas the center-left can seem managerial and technocratic, Trumpists speak to the heart. And they shouldn’t be underestimated. They outmaneuvered the left in both Britain and Finland. Trump claimed the Brexiters “put the United Kingdom first, and they took their country back,” adding, “we’re going to do the exact same thing on Election Day 2016 here in the United States of America.”

But the Trumpists also have weaknesses. They can win power—but they don’t know what to do with it. After the Brexit decision, the leaders of the Leave campaign seemed dazed and confused, and had no plan for what should happen next. The most famous Brexiter, the wild-haired Conservative MP Boris Johnson, had long wanted to be prime minister (a step toward his childhood aim of becoming “world king”). But when British Prime Minister David Cameron announced his resignation, Johnson’s campaign to replace him quickly fizzled out. Johnson was recently appointed foreign secretary and many people are extremely skeptical about his credentials—“a liar with his back to the wall” was the French foreign minister’s description of Boris.

Similarly, after the Finns Party entered the government in Helsinki, they hemorrhaged support, and polls suggest their backing is down to 10.7 percent. The Finnish populists found that governing is a lot harder than campaigning. Wrestling with complex issues like the Greek bailout and the struggling economy, and making inevitable compromises, the Finns Party couldn’t live up to their grand slogans and promises.

Similarly, if Trump wins, there’s a good chance that he will be all at sea. For one thing, he has no experience of managing Congress. Of course, by then it might be too late to stop his agenda.

What would it mean to find the bold and passionate ideas that can defeat Trumpism? It means being pro-immigration but accepting that the movement of people can easily trigger social dislocation. It means embracing the benefits of globalization, while finding new solutions for the myriad economic, political and cultural fractures it causes, and aiding the inevitable losers who suffer. It means trumping the Trumpists with a positive form of patriotism. The progressives can’t be purely internationalist, or as the British poet and cosmopolitan Samuel Coleridge was once satirized, “The friend of every country—but his own.”

If Trumpists can form networks, so progressives can learn from each other, copy or adapt what works, and avoid what doesn’t. A rival group of Finns have emerged to challenge the Soldiers of Odin. The Sisters of Kyllikki, named after a character in the country’s epic poem Kalevala, walk the streets of Finnish towns and seek to build bridges between different communities. Meanwhile, tens of thousands of pro-Europeans marched recently in London, and were cheered by Polish builders and hotel chambermaids. They carried banners in the British style, which read, “I am really quite cross!” “Fromage not Farage,”  and “nothing compares 2 EU.”

Many people say the upcoming U.S. presidential election is the most critical in a generation because of the stark consequences for the United States. But it’s actually more important than that. The United States is now the central front in a global struggle against Trumpism. The battle of Britain is over. The battle for America is about to begin.