It’s rare for a new political party to launch with a functioning political programme. Most arrive with a placeholder name, a half-formed slogan, and a vague commitment to fairness. This one—Corbyn, Sultana, and the scaffolding beneath them—comes armed with a recognisable platform: public ownership of rail, energy, mail; free childcare; rent controls; an end to arms sales to Israel. It’s not a discussion document. It’s a programme. One that could have been lifted (mostly intact) from the 2015 Labour manifesto. That makes it unusually serious. Not in its presentation, which has been uneven, but in its politics. It has positions, not just vibes.

What it doesn’t yet have is form.

The launch drew over 600,000 sign-ups in its first few days. That’s not nothing. But it’s not organisation either. It’s raw potential. And potential decays quickly if it isn’t translated into structure. That means dues-paying membership, clear lines of accountability, internal elections, local branches, and a programme people can act through and not just agree with.

All of this costs money. Serious money. Not just for videos and slogans, but for organisers, legal compliance, media support, materials, translators, staff who know how to run local and then national campaigns without burning out. A national left party can’t run just on volunteers. That mistake has been made already. The Corbyn project was powered by activists but hollowed out by the party HQ. If this new formation is to do more than launch, it has to raise serious funds, and be transparent about where it’s going.

Then there’s the question of who actually carries this thing at the next level. Do the architects of the new party try to run everything centrally? But this ignores the network of left independents, socialist councillors, local campaigns and regional alliances that already exist. Or do they bring them in? If they’re smart, they’ll do the latter. Because if even a portion of the independent left (those expelled from Labour, those who left on principle, those already standing as councillors or mayors) formally joins, this could become a bigger bloc than Reform UK by the time the next general election comes around. It’s not just a numbers game. It’s about credibility. There are people already doing the work, even those still in the Labour Party. Don’t sideline them. Bring them in.

And sell the manifesto now. Not as a consultation document. Not as a “starting point for discussion.” Sell it as a political line. Live through it. Make it the terrain. Yes, adapt and amend as conditions shift. But don’t hide behind process. People want to know what this party believes, what it would do, how it differs. That document (more or less what Labour offered in 2017) isn’t radical because of tone. It’s radical because it names enemies and redistributes power. Treat it as foundational. Campaign on it. Teach through it. Build around it. Every delay in owning it is a delay in becoming real.

The risk isn’t that the policies are wrong. They’re not. The risk is that, once again, the political architecture is being improvised. No constitution has been published. The membership model is still vague. A founding conference is scheduled for the autumn, but whether it will have real deliberative weight (or just serve as choreography) is unclear. The organisers are asking for trust, again, without offering structure in return.

The question of leadership doesn’t help. Jeremy Corbyn still draws crowds, and his moral clarity on Palestine and social justice gives the project gravity. But he is no longer the person to lead a new party. His presence is symbolic, not strategic. Zarah Sultana, by contrast, has political cut-through. She speaks in a language the post-2010 generation recognises. She connects with constituencies Labour has written off: renters, racialised youth, young workers. If there was a mistake in the launch, it was the instinct for joint leadership. These arrangements rarely survive contact with either media or internal politics. Authority split is authority diluted. If this project is serious about future-proofing itself, it should let her lead.

But even that isn’t enough. Because outside Westminster, the Greens are already filling the vacuum Starmer’s Labour has left. On Gaza, on housing, on climate, they’ve become the de facto left opposition in cities, university towns, and many council chambers. If Zak Polanski wins the Green leadership (as seems increasingly likely) they’ll become an even more credible vehicle for young, disillusioned, anti-Starmer voters. The new party will have to decide how to relate to that energy. Ignore them, and split the left vote in areas where both are weak. Coordinate with them, and risk diluting its class politics. Neither option is simple. But pretending the Greens don’t exist would be a mistake. Any serious left formation will need to face the fact that it’s not the only game in town.

In Cymru, the picture is even more complicated. Labour’s grip on the Senedd remains intact, but the terrain is shifting. Plaid Cymru holds space in the national imagination but lacks movement on the ground. Their mix of cultural nationalism and soft social democracy no longer cuts through as it once did. For this new party to matter in Cymru, it will need more than slogans and translated leaflets. It must engage with the realities of Welsh working-class life: post-industrial towns where the unions are fading, language politics shaped by class and geography, frontline workers striking across the public sector.

And now, there’s Reform UK, polling far higher than expected in parts of the Valleys, North Wales, and border towns where Labour has long assumed passive loyalty. This is no longer a protest vote. It’s a political current shaped by absence. Where Labour is absent, Reform fills the silence, with nationalism, grievance, and racialised blame. The new party cannot afford to treat Cymru as a peripheral add-on. If it does, Reform will walk through the door just as easily as it is doing in England. And if the left fails to build something rooted and credible here, we will look back and realise the fight for Cymru was lost before it ever began.

The 600,000 sign-ups are a gift. But gifts expire. If even 5% of those sign-ups become organisers, the new party could field serious campaigns in the 2026 local elections. If they’re not mobilised (into branches, candidate training, canvassing, fundraising, translation work, political education) then the moment will close, and Reform UK will walk through the door the left failed to guard. Reform doesn’t need good policy. It just needs to show up angry. And in too many places, they’re the only ones showing up at all.

So what does it mean to turn this launch into a party?

Set real dues. Publish a draft constitution. Create organisers before you create spokespeople. Get into the towns where Labour’s disappeared and Reform is waiting. Coordinate with the Greens where possible. Contest where necessary. Build in Cymru like you intend to stay. Don’t leave the same people pulling the levers in the dark. And don’t wait for 2017 to come back. It won’t.

Because here’s the truth. Corbynism was too nice. It tried to accommodate the Labour right when it should have destroyed it. It mistook pluralism for unity, treated internal sabotage as misunderstanding, and left entire structures of the party untouched in the name of civility. The leadership never built a cadre. It never imposed a political line. When the attacks came, it hesitated. And when the purge began, there was nothing to hold the line. That can’t happen again.

Left populism without structure is sentiment. Structure without populism is a think tank. What’s needed now is synthesis: a party that speaks clearly, acts decisively, and stays rooted. A politics that can survive betrayal because it doesn’t rely on a single figure. A machine—not for branding, not for nostalgia, but for power.

This new formation might be the beginning of that. It has a manifesto. It has real momentum. It has one more chance.

Even Rod Liddle, one of the right’s most reliable bile merchants, sneered last week that the party would be “lucky to last three months before the first split.” The instinct is to dismiss it. But he’s not wrong to expect fragility. The British left has a reputation for collapse because, too often, it builds personality cults instead of parties, messages instead of mechanisms. What stops a split isn’t unity, it’s structure.

Now it has to build.