Last week, I wrote a general interest piece on the Corbyn–Sultana initiative to launch a new grassroots political party in the UK. After posting it, I realised I had a more personal connection, and a story worth telling.

I was there in 1981.

When the “Gang of Four” – Roy Jenkins, Shirley Williams, David Owen, and Bill Rodgers – strode out of Labour’s crumbling broad church and declared the need for a new political home, it felt like a break with the grey inevitability of two‑party Britain. Labour, under Michael Foot, was veering sharply left; the Conservatives, under Margaret Thatcher, were galloping into free‑market dogma. In between stood millions of voters – decent, pragmatic, social democrats, who wanted neither hard socialism nor hard monetarism.

Along with my girlfriend, I joined the Social Democratic Party because we thought it would be the vehicle for a new progressive realignment. The SDP promised modernisation, pro‑European internationalism, civil liberties, and a politics of reason over dogma. I chatted with David Owen when he visited Durham’s Student Union, and we discussed European integration and mixed economic models. We were going to break the mould.

Of course, the mould didn’t break.

The SDP, despite polling in the mid‑20s, was mugged by Britain’s electoral system. In 1983 we won 25% of the vote but just 23 seats. My girlfriend ran in that election as the SDP candidate in a London constituency and came in second. The Liberal Alliance gave us numbers, but also blurred the brand. By 1988, the merger into the Liberal Democrats marked the end of the experiment. David Owen kept a “continuing SDP” alive for a few more years, but it dwindled into irrelevance. The lesson seemed clear: you can’t break the mould if you can’t break first‑past‑the‑post.

Fast‑forward four decades.

Jeremy Corbyn, a figure I would once have dismissed as unelectable, has just launched a new left‑wing party with Zarah Sultana. The working title is “Your Party” –  a placeholder until the members choose the real name. It’s a start‑up political force aimed squarely at the people Starmer’s Labour has abandoned: young, working‑class voters, trade unionists, Muslim communities, tenants trapped by spiralling rents, and those appalled by Britain’s foreign policy silence over Gaza.

This is not a replay of the SDP. In fact, it is almost its mirror image. Where Owen’s SDP was a break from Labour’s leftward drift toward a moderate centre, Corbyn’s break is from Labour’s retreat to cautious centrism. The SDP sought to cool the fires of Bennite socialism; Corbyn wants to rekindle them, but with 21st century energy, and an unapologetic moral clarity.

The early signs suggest an appetite for it. Within hours of launch, the new party reportedly gained 80,000 sign‑ups. Early polling shows it could attract up to 10% of the national vote and, strikingly, over 30% of voters aged 18 to 24. That’s not a niche; that’s a generation.

The platform is unashamedly radical: public ownership of rail, mail, and energy; wealth taxes; rent controls; and a foreign policy grounded in human rights, starting with an arms embargo on Israel. It’s the politics Labour once flirted with under Corbyn’s own leadership but has now buried under Starmer’s managerialism.

Of course, the familiar spectre of the electoral system looms over this effort too. Under first‑past‑the‑post, 10% of the vote without concentrated geographic strength delivers little in the way of seats. The same mechanics that kneecapped the SDP will bite here as well. Worse, the vote‑splitting effect could deliver seats to the Conservatives or Reform UK that might otherwise go Labour.

This is the main line of attack from Starmer loyalists, that Corbyn is dividing the left and letting the right in. I’ve heard this argument before. In the early ’80s, Labour accused the SDP of doing Thatcher’s bidding. And yes, in some seats we did make a Tory win easier, but that’s the nature of political pluralism: no party owns your vote.

The truth is that Labour in both eras created the conditions for a breakaway. In 1981, Labour’s embrace of unilateralism, its hostility to Europe, and its tolerance of factional extremism drove moderates away. In 2025, Labour’s embrace of fiscal caution, its refusal to reverse austerity, and its complicity in moral abdications on foreign policy have alienated a swathe of the progressive left.

There’s also a difference in energy. The SDP’s strength came from defecting MPs and respected establishment figures. That gave us media credibility, but also made us a party of insiders in exile. Corbyn’s movement is almost the opposite: driven by grassroots organisers, youthful energy, and activist networks built over years in Momentum, trade unions, and anti‑war campaigns. He’s starting with a mass base the SDP never had.

That matters.

Politics in 2025 is not politics in 1981. Social media can turn a well‑phrased message into a viral moment that reaches millions without needing permission from Fleet Street. Independent fundraising platforms can keep a party afloat without deep‑pocket donors. Organised communities can be mobilised quickly in ways we could barely imagine in the early ’80s.

But the hurdles remain. Charisma and clarity are not enough. Organisation, discipline, and a credible electoral strategy are vital. The SDP faltered because we could not translate national polling into local machinery that could deliver seats. If Corbyn wants to avoid our fate, he will need to learn that lesson quickly, and perhaps swallow the bitter pill of electoral pacts with the Greens and others in key marginals.

What draws me, a lapsed social democrat, to this project is the moral clarity. The SDP believed in decency and moderation; Corbyn’s party believes in justice and equality. The former was about making the system work better; the latter is about making a different system altogether. In an age of deepening inequality, climate emergency, and political cynicism, moderation feels inadequate.

In 1981, I thought the centre could hold. In 2025, I’m no longer so sure. The forces pulling Britain apart are not ideological factions in parliament but the grinding realities of low pay, unaffordable housing, public services on their knees, and a political class that treats foreign policy as an exercise in selective morality.

So yes, I will be watching Corbyn’s new party with hope, and with the long memory of someone who’s seen idealism crash against electoral reality before. The challenge will be to harness the passion without losing strategic focus, to avoid the trap of purity politics that comforts the faithful but leaves power to the enemy.

The SDP set out to break the mould and failed. Corbyn’s party may be trying to remould it entirely. If he can unite the moral urgency of the left with the organisational savvy of a winning campaign, this time might be different. And after forty years, I’d like to think the mould is already cracking.