Corbyn may not have had an original thought since 1985 but that does not appear to matter: his old ideas, his back story and amateurism are part of his appeal. In the view of his supporters, his incompetence only makes him more “real” while his challengers only make him seem more principled. Cameron may have barked at him in the Commons to smarten up his appearance but Corbyn is a leader for the #nofilter age whose dishevelled geography-teacher-chic is central to his “authenticity”. To his supporters, he is the ultimate retro politician — he has all the appeal of a record player in an iPod age. 

In this sense, Corbyn has very modern attributes not just in his mode but also his support base. Corbyn’s takeover of the Labour party in the summer of 2015 was not a peasants’ revolt but rather a pensioners’ revolt, overseen by a crew of backbench has-beens. But it has undoubtedly has its greatest appeal among the young, on whom the Labour leadership increasingly relies to do much of its work on the ground. Corbyn (67) and John McDonnell (64) are now the political equivalent of over-the-hill rock stars headlining the Pyramid stage at Glastonbury, feeding off the energy of the youthful crowds as they trudge through their set of self-indulgent prog-rock anthems.

Politics always gives rise to strange alliances but this intergenerational love-match between ageing baby-boom radicals and frustrated millennials is a genuinely new phenomenon. It was not a feature of previous surges in radical youth politics during the Sixties or early Eighties — unless you count Chairman Mao’s Red Guards or Pol Pot’s Khmer Rouge. Nor can we put this down to Corbyn’s unique qualities. His American doppelgänger, Bernie Sanders, inspired a similar surge among college voters despite the Democrat party machine actively working against him. Dismissive of Hillary Clinton’s progressive credentials and out-of-date feminism, it was Sanders, a 74-year-old self-proclaimed socialist, whom America’s young saw as the great hope for the future. Such devotion did he generate that Clinton is already finding it tough to win these supposedly Democratic voters over to her campaign. If the global youth are becoming radicalised, they are turning to really old radicals to lead them.

It is a strange fact that in Britain the voice of our disaffected youth is a pensioner from Shropshire with a fisherman’s cap and a free bus pass. Poor Ed Miliband never stood a chance. He was like the newly-qualified teacher who tries to be your friend but could not control the class, whereas Corbyn is the eccentric and shambolic schoolmaster who turns up late, never marks your homework, refuses to follow the syllabus and inexplicably inspires adoration from his pupils.

Corbyn has become the leader that Russell Brand always aspired to be (with Brand apparently admitting defeat by bowing out of politics). But we should not be shocked by Corbyn’s appeal nor the resurgence of progressive radicalism among Britain’s youth. They are the most economically disenfranchised generation since the 1930s, whose resentment has only sharpened since the EU referendum. They are asset-poor and heavily in debt; their wages have stalled while rents have spiralled. A quarter of graduates are still on around £20,000 a year a decade after leaving university. They are rightly frustrated at governments which have lumbered them with a crippling amount of debt for a degree that does not guarantee them a decent job. And yet, like all radicals before them (and those supporting Sanders across the pond), they are mostly middle-class and white, turning against a system that largely works in their favour and seeking solace in a leader with a similar background.