As politics gets polarised, many polls in Europe and beyond no longer have clear outcomes

Spain’s politics remain in deadlock after the fourth election in four years failed – like the previous one, seven months ago – to return any party, from left or right, with enough seats in parliament to readily form a new government.

As it did in April, the centre-left PSOE party of the prime minister, Pedro Sánchez, topped Sunday’s poll, but fell short of a majority. And while the conservative People’s party bounced back and the far-right Vox surged, the right, too, lacks the numbers to govern.

As Sánchez tries again to plot a path that might break the stalemate, he can at least console himself with the knowledge that he – and Spain – are far from alone: inconclusive elections are becoming the new normal.

Across Europe and beyond, as an increasingly fragmented political landscape becomes more polarised and voters increasingly see issues of identity, not the economy, as the key battleground, countries are finding elections no longer have clear outcomes.

Sometimes, this can mean no government can be formed at all: Spain has been ruled by Sánchez’s caretaker administration since April and that looks likely to continue for some time. Another example is Israel, where elections in September failed to resolve the deadlock left by equally inconclusive polls in April.

Other times, coalitions can be built, but only after increasingly difficult negotiations: the Netherlands (208 days) and Sweden (more than four months) set new records in 2017 and 2018. Belgium has now been 170 days without a government, though that is still some way off its 541-day record after the 2010 elections.

Why is this happening? In part because, from Germany to France, Italy to Austria and Spain to Sweden to Israel, fewer and fewer people are voting for the big, broad-church centre-right and centre-left parties that have dominated their respective national political stages since the end of the second world war.

Spain’s PP and PSOE would once garner 80% of the vote between them; they managed barely 48% on Sunday. In the Netherlands, the three big mainstream parties scraped barely 40% together at the previous general election – roughly the proportion that any one of them might previously have expected.

In Germany’s 2017 poll, Angela Merkel’s mighty conservative CDU and its centre-left SPD rival fared worse than at any time since the 1940s, while in Sweden the Moderates and Social Democrats held up better but still lost ground. In Israel, Likud and Blue and White managed barely 25% of the vote each.

The decline of the big parties has been paralleled by the rise of an array of smaller parties, ranging from far-right, nation-first types such as Germany’s AfD and Spain’s Vox to free-market, Green and far-left anti-austerity parties including Podemos, anti-system parties such as Italy’s Five Star Movement and regional secessionists.

One consequence of this fragmentation (the Netherlands is an extreme example: 28 parties fought the last election, 13 of them winning seats in parliament) is a huge increase in electoral volatility: 41% of Swedish voters backed a different party in 2018 than in 2014, a figure that is not unusual.

Another, with the return of the extremes and the rise of identity politics, is increasing radicalisation – which means non-negotiable red lines and an inbuilt aversion to compromise and consensus, making coalition-building much harder.

Neither major party in Israel, for example, is prepared to work with the Joint List of Israeli-Arab parties, which finished third in the latest elections, just as the centre-right and centre-left in Sweden will not go near the Sweden Democrats, and the PP and PSOE shun the Catalan separatists.

Does this matter? Yes, say analysts, because the flimsy coalitions and splintered legislatures that generally emerge – if they emerge at all – from fragmented systems make it much more difficult to govern.

Of necessity, they involve more parties - and those parties each have very different objectives. That can make it harder for countries to adopt reforms, pursue controversial but necessary policies, or play a decisive role on the international stage.

Until now, Britain’s first-past-the-post electoral system has appeared to protect it from such fragmentation: the proportional representation systems more common on the continent make it significantly easier for small parties to thrive.

But the Brexit earthquake may have destroyed that supposedly stable two-party system, with the surge of the Liberal Democrats, the emergence of the Brexit party and the dominance of the Scottish Nationalists threatening to eat into the big parties’ vote, plus tactical anti-Brexit voting potentially playing a role.

While the Conservatives seem on course to finish as the largest party, they will not be able to forge alliances – so anything other than an outright Tory majority in the Commons may leave Boris Johnson, like Sánchez, bemoaning an inconclusive election, a hung parliament, and no stable government on the horizon.