The biggest danger facing Europe isn’t so much Brexit, or even the “populist wave” sweeping the continent. It is the depressing fact that continental Europeans seem to be losing an appetite to even try to understand one another across national and cultural boundaries. Ignoring or even provoking your neighbour has become a new normal as countries become more and more inward looking.

In recent weeks, I’ve travelled to a number of European capitals. What I picked up is that a fragmentation of minds is under way, even though so many contemporary themes, from globalisation to migration, are the common concern of all Europeans. There is particular pathos to this as the centenary of the 1918 armistice approaches. With a key European parliament election just seven months away, the psychological divisions across the continent seem to be deepening, not diminishing.

This is not just about the tensions between populist and non-populist governments. We know that two camps are pitted against one another: on one side, Hungary’s “illiberal democrat” Viktor Orbán, Poland’s nationalist leadership, Italy’s far-right strongman, Matteo Salvini; on the other, France’s Emmanuel Macron, Germany’s Angela Merkel and the Netherlands’ prime minister, Mark Rutte. This will define the looming 2019 electoral clash. What’s less explored is how, at a grassroots level, people’s perceptions have drifted far from the European “demos” or public realm dreamed of by the creators of the EU.

We have entered a phase where Europeans are encouraged to turn against one another depending on their nationalities

Of course, all politics is inevitably local. And the dizzying volatility of national politics across the continent means that it’s hard enough to keep track of what’s going on in one’s own country – let alone try to seize the complexity of what’s happening elsewhere. There’s only so much news people can consume, and what’s on offer will often depict events through a national prism: social media have the potential to connect far and wide, but by now we’ve seen ample proof that algorithms favour confirmation bias, rather than opening up minds to different takes or sensitivities. In Europe’s patchwork of separate political cultures and distinct national memories, that technological backdrop arguably has an even more polarising effect than, say, in the US.

It’s true that, as anyone travelling from Tallinn to Berlin or Vienna to Belgrade will know, linguistic barriers aren’t what they used to be: the spread of English has provided Europe with a lingua franca, especially among the younger generations. The single market, free movement and the Erasmus student programme have helped millions become more aware of others across cultural boundaries. But those trends of convergence risk being outpaced by political narratives that seek to drive citizens into ever more separated national mindsets.

A few weeks ago, during a debate on Europe in Vienna’s Burgtheater, I made the point that the Austrian foreign minister Karin Kneissl’s association with the far-right Freedom party embodied precisely the danger Europe faces: the go-it-alone message and the danger of democratic backsliding that comes when xenophobic nationalist parties gain power. Sitting on the panel, Kneissl responded by criticising France for its failure to pull its weight by attending enough EU meetings; in other words, by attacking the country I’m from rather than by addressing the issue at hand. Of course, politicians with connections to nativist parties will easily ascribe one person’s opinion to their origins or their passport. Still, it was striking that a government minister whose country currently holds the presidency of the European council would seek to disqualify someone’s point of view by referring to that person’s identity or place of birth.

Something even more worrying is at work in Italy, whose leadership is fast taking the country back to something akin to neo-fascism (its deputy prime minister, Salvini, likes to quote Mussolini). Italy’s drift does not just create headaches for the EU as an organisation, it also sets the stage for growing popular resentment against other Europeans. Having come to power by stigmatising African and Muslim migrants, Salvini’s League has shifted to yet one more target: French and German opposition to Italian budget plans.

Historical resentments that were thought to be long forgotten are bubbling back to the surface. The Brexit conundrum hardly features in the daily preoccupations of continental Europeans, but what does get noticed is how some of the British discourse has started depicting the French as an arch-rival intent on creating as much pain as possible for Britons in their negotiation with the EU. Meanwhile in Poland, anti-German rhetoric is a regular feature of the ruling nationalist party’s narrative – complete with renewed calls for German second world war reparations. To think none of Europe’s intergovernmental squabbling trickles down to grassroots perceptions is perhaps naive.

The popular anger that populists feed on now seems to be deliberately channelled towards a growing list of targets, smoothing the path for what could amount to a European psychological “civil war”. Look at the chronology of recent years: first populists lashed out at the single currency and policies attached to it (Germany’s far-right AfD initially grew out of this in 2012); then came the targeting of migrants (the 2015 refugee crisis was a boon for extremists).

Now we seem to have entered a phase where Europeans are encouraged to turn against one another, depending on their nationalities. Italy’s and Austria’s far-right governing parties may see eye to eye on many European issues, but that has not prevented the two countries from recently reigniting an old dispute over the region of South Tyrol. The paradox, of course, is that not since the end of the cold war have Europeans been confronted with a such a common set of shared challenges: Russia’s aggressiveness, Trump’s disparaging of alliances, climate change, migration, unregulated globalisation, the impact of the technological revolution: you name it. Five hundred million people living within a bloc that proclaimed in 1991 the advent of “EU citizenship” have arguably never shared such an intertwined destiny.

But the problems get discussed within national borders, far more than in cross-cultural or cross-regional ways. The hope is that next year’s European parliament election will open up a continental debate but it may be a long shot. One recent analysis, published by the Brussels-based Carnegie thinktank, warns that by creating a climate of fear, populist parties fuel “xenophobia toward other Europeans”, not just toward people coming from further afar. And there is no such thing as a widely used European public service media organisation that might help bridge perceptions.

The European project was created not only to secure peace among nation states, but to act as an antidote to hostility among its peoples, misunderstandings between them, and sheer ignorance of what neighbours care about and why. In his book Europe: A History, Norman Davies noted that with the transformations of 1989 (it will be the 30th anniversary next year), “the frontiers were open, and minds were opening up with them”. Now is the time to make sure minds aren’t closing up again.

• Natalie Nougayrède is a Guardian columnist