Chris Saltmarsh reviews Russell Warfield’s The Green Socialist: Zack Polanski and the Battle for Britain’s Future — a book by a left-Green campaign volunteer about the man who has pulled the party from ~66,000 members to over 230,000 in a year. It reads most usefully as a map of how Polanski’s own supporters understand the project, and then names the contradictions they would rather not.

What has actually happened:

  • Membership of the Green Party of England and Wales quadrupled after Polanski’s September 2025 leadership win
  • The Greens took Gorton and Denton in a by-election, beating both Labour and Reform UK, and posted their best-ever local results in May
  • Polanski’s own path is short and sharp: Lib Dem in 2015 (during the austerity coalition), Greens in 2017 after failing Lib Dem selection, opposition to Corbyn from the right, then a leftward shift that won him the leadership
  • He is now running in Holborn and St Pancras, aiming to make the Greens the permanent left opposition to Labour

Saltmarsh separates three electoral purposes that live inside the same party and do not agree with each other: supplant Labour, stop Reform UK, or represent a progressive social bloc. He argues only the third is viable. Labour is still the strongest national bulwark against Reform because it can draw from both Green and Reform voters, while Greens and Reform appeal to distinct bases and cap each other’s ceiling. A principled left pole on migrants’ rights, climate justice, and Palestine solidarity is a real position; winning outright is not.

The deeper problem is ideological. Polanski calls himself an eco-populist and has never publicly used the word ecosocialist, even though it is in the book’s title. Eco-populism is a communication strategy — a “people” mobilized against an elite, mostly voiced as 99 percent versus 1 percent. Ecosocialism is an economy inside ecological limits with the profit motive and perpetual growth discarded, which is a rupture with capitalism and implies democratic ecological planning rather than a longer wishlist. Its absence leaves the Greens with no programmatic answer to the remilitarization-plus-AI-plus-fossil-fuel growth model that Andy Burnham’s Labour still runs on.

The closing argument is organizational, and it is the part the British left keeps failing. Conference voting aggregates individual preferences rather than building collective deliberation; those who set policy face no accountability; there is no democratic whip over councillors or MPs, so representatives can ignore members. Saltmarsh’s conclusion is blunt — for ecosocialists, the party’s democracy is not something to celebrate but something to remake.