The European Parliament elections have reinforced the continent's political battlelines.

The pro-European Union forces may say they have held the line, but nationalist-right populists say the wind is in their sails.

Voters have abandoned centre-right and centre-left groups; some have flocked to the greens, others to the far-right.

The result tells us that the old economic class-war politics of left versus right has given way to culture wars over climate, trade and particularly immigration.

Nationalism haunts Europe

The results across Europe are uneven. Voter turnout was the highest in two decades. Overall, pro-EU parties dominate the Parliament, yet in several significant countries, the anti-EU forces have increased their vote, among them the Brexit party in Britain.

One powerful theme emerges: identity.

This election tells us that nation matters. Borders matter. The tribe matters.

It is potentially perilous territory. Nationalism is the spectre that has haunted Europe and contributed to the bloody wars of the 20th century.

Passions again run high and that is fertile ground for populists who capitalise on fear and anxiety.

The language of nationalism — faith, community, family, history, culture, race and ethnicity — comes readily to them.

People who have seen their factories close down, their jobs lost, who feel displaced in their own countries are listening and they like what they hear.

In Italy, Matteo Salvini, leader of the triumphant far-right League Party, speaks of a "wind of positive energy", which he says "has brought in fresh air".

I am reminded of the 18th century politician and philosopher Edmund Burke, who warned of the French Revolution that "the wild gas, the fixed air is plainly broke loose".

It is wise to heed the words of Burke, considered the father of conservatism — so much of what he wrote speaks profoundly to our age.

While others saw revolution as a triumph of liberty, he cautioned that liberty may lead people to "do as they please: we ought to see what it will please them to do".

The EU elections have historically had a low turnout. ( AP via MTI: Zsolt Czegledi )

The 'age of anger'

Nationalism speaks emotionally to belonging. It is a repudiation of the "citizens of anywhere" in favour of the people of somewhere.

Yet it courts the darker impulses of xenophobia, racism, sectarianism, that turns politics into a tribal warfare of us versus them.

There is an argument to be made that the nationalist narrative is ascendant globally.

Its promise to return nations to a lost glory, to turn back the tide of globalisation and put their countries first — to make them great again — is a siren call for people who feel displaced.

It has hastened the return of the political strongman — the authoritarian leader — from Vladimir Putin in Russia to China's Xi Jinping, Duterte in the Philippines, Turkey's Erdogan, Viktor Orban in Hungary.

Apart from Mr Xi, all have won power at the ballot box.

Donald Trump has been placed in the same company — America's system of checks and balances makes that a stretch — but the US President has certainly given indications of being comfortable with authoritarian figures.

This is the politics of our time; what has been called the "age of anger".

It is a long way from the end of history that was promised after the Cold War.

The cosmopolitan dream of liberal democracy, open borders, free movement of goods and people, multilateralism, is being tested by a return of history: old fault lines are stirring.

Not for nothing does the independent watchdog Freedom House now count 13 straight years of declining freedom in the world.

It says we are in a democratic recession. Hungary's Orban now declares his country an "illiberal democracy".

If Edmund Burke speaks to the caution of conservatism then Carl Schmitt speaks to the nationalist impulse and more widely to the politics of identity right across the political spectrum.

The 1930s German philosopher said politics was not about adversaries or opponents, it was about enemies. It was a battle of good versus evil. The high point of politics he wrote, arrives when "the enemy is in concrete clarity, recognised as the enemy".

Identity is playing out in many ways: at an international level, as a battle between nations and within nations, as various identity groups form around race, ethnicity, sexuality, gender, each seeking their own ends in a competition to cancel out each other.

Whatever form it takes, it undermines the ability to find common purpose beyond our differences. Within nations, it erodes the sense of civic citizenship; internationally, more strident nationalism makes it more difficult to reach consensus around critical issues of security, trade or climate change policy.

The right is playing identity politics better

Both progressives and conservatives — left and right — play with the politics of identity, but it can be argued the right is playing it better.

The election of Mr Trump and the Brexit vote were political shock waves.

Progressives are struggling to find a story, their cosmopolitan liberalism looking elitist.

As Labor's election loss here showed, a big change agenda doesn't work if the people don't believe in the change on offer.

At best, progressives appear out of touch, at worst, as Hillary Clinton's "deplorables" comment showed, they don't seem to like the people they seek to lead.

Progressives fall into the trap of blaming the voters for the outcome.

There is a big realignment in global politics, the European elections are the latest example.

What some dismiss as the scourge of populism might instead be just popular. People are turning out in increasing numbers to vote and calling them wrong or deluded isn't a good enough response.

Remember the words of the German poet Bertolt Brecht: what would you do, "dissolve the people. And elect another?"

Stan Grant is the ABC's global affairs analyst.