TO UNDERSTAND Austria, visit the Karl-Marx-Hof. This vast municipal housing complex in Vienna is still riddled with bullet holes—not from fighting between Russians and Germans in 1945, but from a little-known civil war in 1934, when Austrian leftists and conservatives took up arms against each other. After the second world war, the country adopted a political system designed to prevent this from ever happening again: the Social Democrats (SPÖ) and the Christian Democrats (ÖVP) would rule together and divvy up public offices under a system known as Proporz.

For 43 of the past 72 years the two parties have run Austria jointly, in grand coalitions. Their networks politicise everything from school boards and business groups to social clubs and unions. The result is a uniquely corporatist country.

Today, however, that system is breaking up. Other parties—first the far-right FPÖ, then the Greens, then the liberal NEOS—have challenged the old duopoly. Both the SPÖ and the ÖVP have lost members. Economic stress adds to the pressure. A decade ago Austrian unemployment was a little over half that of Germany; now it is 50% higher. On May 10th Reinhold Mitterlehner, the ÖVP vice-chancellor, resigned and brought down the dysfunctional SPÖ-led grand coalition. Elections will take place on October 15th. “What is happening in this country?” marvelled Profil, a news magazine: “Austria is unrecognisable, and redefining itself breathtakingly fast.”

At the heart of the drama is Sebastian Kurz, Austria’s 30-year-old foreign minister, its most popular politician and the ÖVP’s new candidate for chancellor. In one sense, he is a product of the old-fashioned associational system, having soared through his party’s ranks as head of its youth organisation. He turned this from a stagnant backwater into a dynamic network of local groups, putting on parties, pub nights, bike rides and various other opportunities for teenagers and 20-somethings to get it on with one another. In 2013 his youthful, liberal base, centred on Vienna, propelled him to the post of foreign minister. He then won over the party’s right-wingers by taking a tough stance on immigration.

Yet Mr Kurz is also determined to break Austria’s old political architecture. He accepted his party’s crown only after its bosses had agreed to several demands. These include the freedom to transform the ÖVP into a list of candidates, pick names for that list, bypass its powerful state bosses and formal interest groups (known as Bünde) and set its policies. Having soared in the polls (see chart), he is now trying to persuade prominent figures in NEOS, the Greens and civil society to join his list. Though his manifesto is a closely-guarded secret, insiders hint at liberalisations of Austria’s schools, labour market and transfer payments. “Taking money in taxes and paying it straight back in subsidies is wrong,” Mr Kurz argues. Christian Kern, the SPÖ leader and current chancellor, is more defensive of the old model: “It made Austria strong”, he says. He suggests that Mr Kurz is more image than substance, and doubts whether he can escape the old ÖVP structures. But like his rival, Mr Kern is a businesslike type who reckons Austria’s paternalist model is dying. “In the past it ran from cradle to grave: you would spend your free time in the Alpine club, at work you would be a member of an SPÖ or ÖVP trade union, from the nurseries to the emergency services everything was parcelled up. These connections have dissolved dramatically.” Mr Kern’s response is what he calls Plan A, a package of liberalising economic reforms and infrastructure investments. Will Mr Kern or Mr Kurz succeed in remaking the system? Critics accuse the former of being a game-player whose grand plans amount to little. And they accuse the latter of merely rebranding the ÖVP. (Important tests include whether he omits unimpressive ÖVP placeholders from his list, whether he can persuade his party to support gay marriage and whether he can stand up to the teachers’ Bund in support of education reform.) Of the two, Mr Kurz is the most ambitious. But the real barrier will probably be that of coalition formation. Messrs Kurz and Kern may agree, largely, on what is wrong with Austria, but after ten years of grand coalition their parties hate each other. Both would like to form a government with NEOS and the Greens, but the numbers look unpromising. That leaves the FPÖ, with which both the ÖVP and SPÖ govern at state level and with which both are willing to form a federal government in October, well aware of the diplomatic opprobrium this would attract.

Both of Austria’s prospective leaders accept that the country’s political system is breaking up. The problem is that, unless polls shift, whoever wins will probably be saddled with a government too weak to allow a thorough programme of reforms. Austrian society is evolving. But whether its politics can keep up is uncertain.