The Greens have a strong support base within social movements. Image: Flickr / Lee Nichols

A few weeks ago Natalie Bennett gave an excruciating interview on an LBC show. But however much it looked like the wheels were coming off the Greens’ carbon-neutral bus, that interview won her my vote. Because no matter how screwed up her numbers were, the commitment was there to build half a million new social homes. It was bold and visionary and also a desperate necessity. ‘How will you pay for it?’ asked a brace of commentators. As a first-time voter belonging to Generation Rent and watching thousands of people displaced from my city due to housing costs while millions languish on waiting lists, I was asking a different question. How will we pay for the alternative?

Housing is, perhaps, one of the main reasons I’m voting Green on Thursday.

It is not the only one. Firstly, I refuse to give in to the ‘Labour to keep the Tories out’ line. My faith in Labour may have faltered some years ago, but I could not have expected to see Ed Miliband posing on a metal gallows with a giant tombstone upon which ‘Controls on immigration’ was etched (alongside other more vapid non-pledges.) Then there’s Labour’s work and pensions spokesperson proclaiming that she couldn’t give two hoots about representing the unemployed, while refusing to commit to restoring the Independent Living Fund. There’s Labour’s Orwellian language redefinition - the pledge to ‘ban exploitative zero hours contracts’ is a pledge to ban only those zero-hour contracts deemed by Labour to be exploitative, rather than actually banning them.

The same for unpaid internships, which I am told are used at Labour HQ. This is before we even get to the vicious internal culture of the party - the game playing of the cliques surrounding Miliband, the campaign against the SNP which has been led by hypocrisy and smears rather than principled disagreement, the bullying of dissenters from Redcar to Tower Hamlets, and so on. Labour continues to hold the left because it can use the Tories as a threat to keep its own side in line, and because it claims to bear an institutional link to the working class through the trade unions. Er, when was the last time Labour actually supported one of those unions going on strike?

To dwell on Labour overly, though, would be to repeat the politics of negativity that have overshadowed this election. We need positive reasons to vote, and we need a vision.

I’ll come back to housing. About a mile down the road from where I grew up, Southwark’s Aylesbury Estate is due to be smashed to pieces to make way for ever more luxury flats. (At the Aylesbury a makeshift banner hangs over the place, the lament of a former resident: ‘They’re all lying fuckers and I’m not voting for any of them until they fix the lifts.’) Elsewhere adverts targeted at a new generation of spivs gleefully boast that there will be no social housing in the area to tarnish their customers’ glossy new apartments, and Labour and the Tories sit there and let it happen. This is not just about affordable homes - it is about class, it is about culture, it is about sustainability and it is about the sort of city we want to live in. And I trust the Greens to have that in mind, to genuinely go about creating places where people want to live.

Ultimately, it comes down to austerity. We have two Westminster parties that agree on the fundamentals of how one runs a society. The manifestoes are different, the scale of cuts are different (and that matters a lot) but regardless of the anti-austerity views of many Labour (and indeed Tory) supporters, a Green vote is a vote for the largest party that stands up to the consensus on cuts. That’s a message that needs to be sent this election, because a deranged and pathological obsession with the deficit has led to untold damage being wreaked upon our society. The closures of schools and libraries and hospitals, the brutalisation of suffering people through the benefits system, the scrapping of jobs and the facilitation of an underemployed, underpaid workforce have all been justified and explained by the need for a ‘stronger economy.’ And so as intangible as an ideological conception might be, registering a solidly-sized vote against the ideology of austerity is crucial as we move forward in the next five years.

That’s not the only area where the Greens are consensus breaking - I’m voting for the largest party that believes you should stand with migrants rather than cheaply pandering to Ukip voters, I’m voting for the largest party that recognises the importance of fixing the climate crisis, and I’m voting for the largest party to make a commitment as simple as ensuring everyone’s wages are enough for them to afford to live on.

The Greens won’t win. But their electoral success can serve as part of a platform for building movements for social and economic change outside of parliament. It is a way to use this election to demonstrate support for principles – the most fundamental being that we solve a crisis by helping people out of it, not punishing them. It’s a way to build an alternative.

That Bennett interview showed that while she might forget numbers (that were produced amply and well later), she would not forget principles. That’s the message of hope to all of us who feel locked out of our broken, detached, cynical political system.