It probably won't join a government, as that would cause an immediate crisis for the organisation, which thrives on its ideological incoherence. Like the original Five Star, once tainted by unpopularity, it would be rarely be heard or thought of again.
As a party with a strong "anti-establishment" flavour (and flavour is very much the word for it), Five Star attracts a lot of support from younger voters, and quite a lot of traditionally centre-left-voting blue collar workers.
The dispensation of the centre media is that Italians, especially young people, have just seceded en masse to the "populists", "anti-establishment parties of the left and right". According to CNN, "the fascists did scarily well". We'll come back to this last point, but for now I'm interested in what constitutes this figure of "populist", "anti-establishment" politics for the press.
By and large, there is a tendency to treat it as a crude generational war, politically indiscriminate in its resentment. This is roughly how The Economist, voice of the capitalist centre, represents things, such that everyone from trade unions, to mainstream parties, to "an ill-defined 'ruling class'" is blamed by these angry youths for the generational gap in prospects.
As always, the generational cliches contain an element of truth. Young Italian workers suffer from the highest levels of youth unemployment in Europe, and over two thirds of them are so poor that they have to live with their parents. There is also at least some measure of truth in the idea that this social resentment has no definite political direction for the time being.
It bears stressing just how structurally incoherent Five Star is. The Guardian is worried about it being pro-Kremlin, but only a few years ago, as the historian of Italian politics David Broder points out, it was supporting Pussy Riot. It's been traditionally eurosceptic, but it has backed off from its commitment to a referendum on the eurozone. It mixes some 'post-materialist' concerns, more typical of the Left, with hippy marginalia, racism, flirtations with fascist parties (and, briefly, with the Liberals in the European Parliament), and a fixation with e-democracy as the answer to an impregnable political elite.
Its voting base reflects this incoherence. As Paolo Mossetti has pointed out, more and more of its voters self-identify with that tendentially empty signifier, 'centrist'; but the party is also unique in drawing voters from across the spectrum, right to left. They are split on Europe, immigration, and taxation. Beyond the ideological vacuity, the organisation is itself strangely vapid. There have been moves to professionalise the upper apparatus of the party, but it has no cadre, it has no grassroots organisation, party militants have very little role in making sure that the nominal 'direct democracy' of the organisation actually bears results. This organisation would melt on contact with office.
However, let's remember what didn't just happen. First of all, pace CNN, there was not a fascist breakthrough. Not, in any way, to minimise the serious escalation and mainstreaming of vicious racism in Italian public life, nor the barbaric discourses around refugees, but it is simply not the case that fascism has just been 'normalised' in Italy. CasaPound, the main fascist group hyped across the continent, got something like one percent of the vote. The Lega Nord did much better, and is right-wing and racist, but not every racist party is fascist. The Five Star Movement isn't coherent enough to be a fascist organisation. Arguably, two general elections ago, things were looking a lot more worrying.
Secondly, what Perry Anderson calls, with admirable contempt, "yuppy simulacra of populist breakthroughs", did not materialise here. Matteo Renzi was supposed to be the young pup, the Macronite outsider trying to break the grip of the old privileged segments, both in the state and in the workforce. For example, the idea that the unions are part of the establishment was essential to Renzi's propaganda during the campaign for his "Jobs Act". Renzi argued that they were a conservative bloc, like the 'vested interests' he was battling in the state. He said they only defended the privileged workers while letting the precarious remainder rot. So, in a country where more than two thirds of young people live with their parents, and with record levels of youth unemployment, his Thatcherite revolt would get the union jackboot off their young necks.
The unions, while staging mass protests against this policy, have also responded to the propaganda attack by aligning itself with the rights of precarious workers. The CGIL leadership mocked Renzi's purported defence of 'Marta', a typical precarious female worker with no rights, by producing a t-shirt reading: 'I am Marta'. Precarious youths, the CGIL argued, had been held down, not by unions but by the employers who exploit precarious labour. It's also worth saying that the unions do, in fact, have some role in organising and defending what are called "atypical workers"). And that even extends to some limited attempts to include migrant workers, albeit far from adequate to achieve effective class solidarity. This contrasts with Renzi's government, which both mandated the exploitation of migrant workers, and participated in anti-immigrant chauvinism for electoral purposes. It is worth adding one other point. Italy has a very high rate of labour emigration, as workers try to break out of Italy's subordinate and declining position in the EU division of labour. Despite this, and an overall declining rate of union density, Italy is one of the few countries in the EU where the average age of union members is declining.
Nonetheless, Renzi campaigned both for his constitutional referendum and for re-election on the basis that he was the pugilist who would smash the stalwarts of the old order. It's fair to say that this strategy, the Macronite approach, actually depends on the idea that this youth "populism" is shallow and apolitical. In no other way could such a senior politician claim 'outsider' status to advance a neoliberal agenda that would once have been deemed radical right but now has the centre-left stamp of approval. And it didn't work, either in the constitutional referendum, or in the election.
So, neither the centre, nor the fascists, had a good election. Lega Nord did well, as did Forza Italia (Berlusconi's bunga-bunga party), but even they didn't do as well as expected, since they seem to be far short of the majority they need to govern.
So what did happen? The truth of the category of "populism", often casually applied to a bewildering variety of forces, is that there is on-goingly a crisis of representation (or, of mediation) in most European and North American capitalist democracies. In that context, the Left has often been able to expand its political space while defending a distinctive class politics. This is true, at least, insofar as it addresses this widespread belief, especially among traditionally centre-left voters, that we are not being represented. Whether it is Podemos, Syriza, or Corbyn's Labour, there is almost always an argument about democracy and representation, and the need for existing political parties to be grounded in and responsive to popular self-organisation.
Where that space should be in Italian politics is, of course, a spectral absence. The collapse of the historically powerful Italian Communist Party, was followed by Rifondazione's catastrophic decision to join an austerian, militarist, centre-left government (the 'historic compromise', first as farce, second as fucking idiocy) resulting in its own demise. That ground has been owned by these dubious chancers in Five Star since the global crash, facilitated by their origins in various social movements. Notably, their schtick about e-democracy, wherein citizens are supposed to be able to use the affordances of the internet in order to propose and craft legislation, resonates with some of the ideology that came out of Occupy, the Indignados and the movement-of-the-squares.
The thing is, the "populist moment" will pass, as these things generally do. The centre-ground will be re-composed on a new basis, however fragile and dysfunctional. Effective 'populist' challengers, by shaking up the power bloc, often help birth the new consensus. The impasses of representation will be resolved in new ways, as the state adapts, and the ideological initiative passes to new platform media. The new centre would probably incorporate a lot of "digital democracy" ideology, while a nebulous feeling of 'participation' can be contrived through social media strategies.
One of the highly ironic fates of Five Star could be, precisely through its role as a permanent catch-all outlet for 'hysterical' protest, that it allows for the constitution of a new master.