Good ideas tend to be copied, and by that measure Brexit is a dud. The UK experience has not inspired copycat secessions from the European Union. It is not studied as the blueprint for what Michael Gove anticipated in 2016 as a “democratic liberation of the whole continent”.

There are plenty of Eurosceptics elsewhere in Europe, but they have swerved away from the British example. That is partly an accommodation to pro-European public opinion in the other 27 member states. After all, the first rule of populism is to be popular. France’s National Front (now rebranded National Rally) has jettisoned talk of “Frexit”. Matteo Salvini, Italy’s far-right deputy prime minister, no longer agitates for a return to the lira.

It gets harder to sell ‘remain' as an antidote when so many EU countries are incubating virulent strains of Faragism

Anti-immigrant parties, often with roots in fascist and neo-Nazi organisations, have encroached on the mainstream in pretty much every European country. Ultra-nationalists are the main opposition in Germany; in Austria they are in coalition government. Democracy in Poland and Hungary has been twisted out of shape by authoritarian regimes that suffocate political opposition, vilify dissent and foment racism, Islamophobia, homophobia and antisemitism.

This emergent league of xenophobes is bound by few taboos, but it does not seek to dismantle the EU. That is not a badge of moderation. It reflects a strategic judgment that illiberal causes are better advanced from within the union, because leaving the club is a fast-track to diminished influence. (A point well illustrated by the UK experience.) Next week’s elections to the European parliament are likely to boost the profile of radical nationalists. They don’t need to achieve spectacular breakthroughs to have an impact. It is sufficient to instil panic in moderate parties, which then mimic the populists’ rhetoric and co-opt parts of their agenda.

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That trend is well advanced in immigration debates. In many countries “Europe” is defined, explicitly or in coded terms, as a white Christian entity with values that are undermined by Muslim interlopers. It’s a formulation that necessarily skips over Europe’s 20th-century record of achieving relative religious homogeneity by industrialised murder. It reflects also ideological cross-fertilisation of European and US nationalisms. Hungary’s prime minister, Viktor Orbán, was effusively received in the White House earlier this week. Donald Trump praised a fellow “tough man” on immigration, who has admirable policies “with respect to Christian communities”. Such developments are disorienting for British pro-Europeans. It gets harder to sell “remain” as an antidote to the politics of Nigel Farage when so many EU countries are incubating their own virulent strains of Faragism. For the same reason, leavers crave success for any movement that undermines the EU’s moral authority.

Since the UK can expect no material benefits from Brexit, politicians who are wedded to that course want Brussels to be mired in crisis. It makes Britain’s choice to absent itself from the top table look less foolish. That impulse will be on display after next week’s MEP ballots. Eurosceptic Tories will breathlessly narrate the results as a tale of surging anti-Brussels revolution across the continent. The walls are coming down, they will cry. All the more reason to get out quick.

The reality is likely to be less dramatic. Conventional European politics has not been abolished. Social democrats, liberals and moderate conservatives will still probably dominate the European parliament. There is a tendency in Britain to scour continental politics for proof that nativist reaction is on an unstoppable march, disregarding the motive and number of voters who hold the line for moderation. Much reporting on Spain’s election last month privileged the 10% tally for Vox, a new far-right group. While that was a significant and alarming development, it was also lower than polls had forecast, and the headline result of the ballot was victory for the country’s long-established centre-left Socialist party.

Anti-Brexit feeling expected to help SNP in European elections Read more

There is no denying a sinister pattern of resurgent nationalism across Europe, but it is neither accurate nor helpful to depict it in fatalistic terms, as if the continent inevitably cycles through harrowing darkness every few generations and, tragically, it is now our turn. It is also misleading to view the challenge exclusively as a crisis for EU institutions. That is how Brexiteers would like it to be framed. It plays to a self-mythologising view of Britain as a place of innate moderation, immune to the kind of ideological excesses found among cold-hearted Germans and hot-blooded Italians. There is an undeclared boundary between vulgar, shaven-headed nationalism and a genteel, tweedy kind; between the Ukip that Farage feels he must disown and the Brexit party he has founded instead. In terms of the underlying prejudices, the distinction is less clear.

Does that make the UK more tolerant than other countries, or just more hypocritical? The forces convulsing our politics are not unique to these islands. Brexit is our particular cultural manifestation of conflicts and stresses that are expressed in different ways across Europe and in the US. And the conflict will not be resolved by withdrawal from the EU.

Two lessons from history are relevant here. First, giving aggressive nationalists everything they want has never succeeded in quelling nationalism. Second, Britain has never avoided entanglement in European crises, although it has often been tempted to try. The European project, conceived in the 20th century as a vehicle for the elimination of conflict between nations, is facing twin threats: the rise of chauvinist, authoritarian forces within its borders, and extraordinary political sponsorship of that agenda by a US president who prefers the company of despots to that of democrats.

In that light, the strategic and moral choice facing every British politician is whether to be allied with the wreckers of liberal Europe or with the resistance.

• Rafael Behr is a Guardian columnist