JOHN LANCHESTER’S novel, “Capital”, provides a vivid portrait of life in a street in south London in the run up to the 2008 financial crisis. The residents watch with delight as the value of their houses rises ever upwards (“Having a house in Pepys Road was like being in a casino in which you were guaranteed to be a winner”). But there is trouble in paradise. The residents start receiving mysterious messages through their letterboxes proclaiming: “We want what you have”. Soon the messages are accompanied by videos and the tone becomes more threatening.

Mr Lanchester’s novel helps to solve the biggest puzzle in British politics: why the vast majority of young people voted for a 68-year-old who has spent his life flirting with organisations such as Sinn Fein and Hamas and backing hard-left causes like the public ownership of the means of production. One interpretation of Jeremy Corbyn’s rise, popular on the left, is that he is satisfying a pent-up desire for “real socialism”. But this ignores the fact that many people voted for the Islington MP despite his policies, not because of them. Mr Corbyn is a long-standing critic of the European Union who did as much as he could to ensure that Remain would fail while pretending to support it. Another interpretation, popular on the right, is that his supporters are woolly minded virtue-signallers, determined to prove how compassionate they are while ignoring the fact that Corbyn-style policies have invariably led to disaster. This ignores the fact that millennials have suffered more from the long stagnation that followed the financial crisis than any other generation. They have reason to be angry.

The most intelligent explanation has been provided by John Gray in the New Statesman. Mr Gray argues that Corbynism is “populism for the middle classes, serving the material and psychological needs of the relatively affluent and the well-heeled”. Far from being a repudiation of Tony Blair’s policies, Corbynism represents the completion of the takeover of Labour by middle-class people who put their own interests (such as free university education) above those of the working class. But Mr Gray’s strictures miss an important point: most young Corbynistas are not so much settled members of the middle class as frustrated would-be members. Ben Judah, a millennial-generation journalist and author of “This is London”, points out that members of his generation are angry that they have done everything they were told, from studying hard at school to going to university to trying to get a respectable job, but are still holding on by their fingertips.

The problem starts with Pepys Road. It is getting ever harder for young people to get a foot on the property ladder or find somewhere decent to rent. Thirty-year-old millennials are one-third less likely to own their own homes than baby boomers were at the same age, and spend £44,000 ($58,000) more on rent in their 20s than baby boomers did. The problem then extends to the workplace. The young have been on the sharp end of two economic shocks: the 2008 crisis, which squeezed living standards, and a technological revolution, which is doing for middle-class jobs what mechanisation did for working-class ones. Automation is hollowing out entry-level positions as companies use machines to do the routine tasks, such as searching through legal precedents or examining company accounts, that used to be done by junior employees. Companies of every type are cutting costs by ditching long-term perks such as defined-benefit pensions.

These problems reinforce each other. People who are subjected to flexible work contracts find it almost impossible to qualify for a mortgage. They are magnified by the London effect. Young people flock to the capital, where the best professional jobs are concentrated, but exorbitant property prices force them to migrate to the farthest corners of the city or to share with strangers. And they are curdled by generational antagonism. The Resolution Foundation, a think-tank, calculates that people aged 65-74 hold more wealth than those under 45, a group that is almost twice the size. Browse the Facebook pages where young Corbynistas hang out and you do not find hymns of praise to the workers’ control of the means of production, but laments for the indignities of modern metropolitan life and jeremiads against baby boomers who grabbed all the cheap houses and got free university education into the bargain.

You say you want a revolution

As it picks itself up after the debacle of the election, the Conservative Party can take some hope from the bourgeois nature of these complaints. All is not lost so long as the party can update its promise of a property-owning democracy to suit the new generation. Ageing cabinet members who have done well out of the past 30 years should be replaced by young people who might have some experience of student debt and out-of-reach house prices. The Tories need policies for the frustrated middle class, particularly building new homes, including on the green belt. They also need to expose the contradictions of Corbynism. Far from democratising the bourgeois dream, Mr Corbyn’s policies would quickly kill it. Empowering trade unions would produce disruption, particularly of public services. Abolishing university fees would make it harder for Britain to compete as a knowledge economy. And drastically increasing public spending would damage international confidence and risk capital flight.

Time is running out. Mr Corbyn continues to mesmerise his young supporters with offers of free tuition and well paid jobs. The Conservatives continue to flail around offering bribes one minute and defending austerity the next. And the political class as a whole ignores the deeper causes of Britain’s stagnation, from stalled productivity to a failure to produce high-growth companies. The most likely outcome is that Britain will add an experiment with hardcore socialism to its experiment with Brexit. Then, the relative deprivation suffered by Mr Corbyn’s middle-class fans will be the least of the country’s problems.

Economist.com/blogs/bagehot