There’s one letter missing from Martin Kettle’s article (If you think a progressive alliance will save us, better think again, 30 December): an S. For the way forward is not one nationwide progressive alliance, but rather multiple progressive alliances. To achieve an overarching national agreement is probably impossible. But progressive alliances can and already are forming – in individual parliamentary seats, across counties, across cities, sometimes at a council level, sometimes at parliamentary level. They’ll have different compositions in different places, according to local circumstances, but will be all the stronger for that, and more resilient. If talks break down or promises are broken in one place, it won’t bring the whole edifice down.

As for what it is for: getting rid of the Tories is a worthy goal, but a bigger, and even more important, prize is getting a fair voting system; electoral reform that will finally give Britain a democracy, a government that reflects the will of the people. Neatly, that would then remove the need for electoral alliances, for a PR-majority parliament, with a genuine will to act, only needs to be achieved once. That’s a prize worth sacrifice and political pain along the way.

Natalie Bennett

Former leader, Green party of England and Wales

• In your interview (29 December), Jeremy Corbyn claims the victory in a council byelection in Telford on 8 December was evidence that Labour can perform well after the setbacks of Richmond Park and Sleaford. Only Telford was evidence of one thing: the progressive alliance in action. Labour almost certainly won the seat for the first time ever because a local deal was negotiated with the Greens and the Lib Dems, neither of whom stood a candidate. All the anti-Tory votes had one candidate to back and that Labour candidate won. The lesson is not that Labour can win alone, but that working together, the progressive parties can stop the Tories and introduce a new form of politics with the introduction of proportional voting. Will Jeremy and Labour learn that lesson in 2017 or keep on losing?

Neal Lawson

Chair, Compass

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