In Brighton, a few months after Jeremy Corbyn first became an MP, Neil Kinnock was elected Labour leader to rescue the party following a general election disaster. Sunday’s conference opener in Brighton was exactly the same, except that it was completely different.

Daunted by the task ahead in 1983, Kinnock leapt into the sea and tried to swim to France. Had he not been beaten back by the waves and forced to spend the next nine years fighting people like Corbyn, who knows? Rightwing defections and leftwing insurgency might have left no Labour party to meet in Sunday’s encouraging sunshine.

Apart from better weather, the day’s main difference was that the leftwing insurgents have finally done it. They have stormed the Winter Palace of New Labour Elitism and installed their own grey-bearded leader. A quietly unassuming man, he slipped on and off the platform barely noticed. It suits him.

That is another difference. Most leaders feel the strain. Leader Corbyn exudes a Zen-like inner calm as the scenery crashes around him and oligarch newspapers excavate his career and love life. Nothing fazes Jez. He has amsirahc, the opposite of charisma.

In the Observer he was photographed not only holding a marrow (Bake Off’s Mary Berry will get a smutty joke out of that) but expressing neo-liberal views on how to grow a really big one: you have to sacrifice all the others, the allotment buff explained. Rupert Murdoch could not put it better.

Jez was equally affable, bland even, on BBC1’s Andrew Marr Show. Had not John McDonnell once said that bankers’ kids should all be dispatched to re-education camps in Lambeth? Not at all, replied Zen Jez, his shadow chancellor had been misquoted. It was to Islington.

And so it went on along the seafront. Tense meetings of the national executive in smoke-free rooms, rival fringe meetings packed to overflowing, not-so-coded attacks and reassuringly Old Labour compromises and prevarication, redolent of the now banished Bad Old Days.

As with the equally flattened Lib Dems and Ukip, the mood was strangely upbeat. Elderly delegates who have not felt so happy since Michael Foot became leader embraced young Corbyn acolytes who have never heard of Foot. Was he deputy PM under Margaret Thatcher? Or was that Les Dawson? At the eye of the storm the leader remained calm.

At one lunchtime fringe, the leftwing comedian Mark Steel summed up the fingers-crossed mood of the conference (so far) when he asked: “Why does Jeremy Corbyn, a cyclist from Islington who spends his evenings at an allotment holding a marrow, frighten them so much?”

The unions’ Mr Big, Len McCluskey of Unite, provided an answer: because Jeremy gives people hope and confidence that, all over the world, Syriza, Podemos, America’s Bernie Sanders and Jez can bring austerity to an end. It is a moving article of faith, details to come later.

But the disconnect with the recent past was still visible. Impassioned delegates who feel they have “got our party back” after 30 years of Tory Lite mourn the wicked Tory removal of allowances, credits and benefits that protected the poor.

Rarely acknowledged is that the same benefits were created by unpersons Blair and Brown, hardly mentioned. Corbyn and McDonnell “live in the real world, they understand the real world. Previous leaders had to have the real world explained to them”, said McCluskey, whose last exercise in king-making led to Ed Miliband.

Feisty Harriet Harman (even posher than Jeremy) was an extreme example of this double-thinking. Denounced before lunch for her Corbyn-boosting abstention on the welfare bill, the outgoing deputy leader was later praised to the skies for her fighting feminism, tribute video included.

Welfare bill? What welfare bill? Jez, who voted against the bill, gave Hattie a kiss and a big bouquet of flowers that he probably hadn’t grown himself. The old smoothie, he is learning the low arts of PR.

It was a good afternoon for tough women. The conference also heard from Angela Eagle, the shadow, shadow chancellor, and from Kezia Dugdale, unlucky enough to be Labour’s new leader in Scotland, but brave enough to say that Corbyn’s Labour now has “more members than at any time since Tony Blair”.

In changing times the conference also cheered a fraternal visitor from Dublin, who said: “ It would still be illegal to use a condom in Ireland if it were not for Labour.” It may not be what Clem Attlee had in mind, but it was progress. Another speaker was Emily Brothers, Labour’s first transsexual candidate. She was cheered after saying: “All I am trying to do is be me, be authentic.”

That’s probably Zen Jeremy’s plan too.