It’s not too late to stop Brexit. Saturday’s march will force politicians to hear us

Last weekend Tim Shipman, the political editor of the Sunday Times, tweeted: “The urge to march for things and against things is one I have never understood. Why not write a letter instead?”

He may have been referring to the start of the March to Leave, Nigel Farage’s much-derided venture that saw a handful of bedraggled Brexit supporters trudging through the rainswept and muddy countryside. But Shipman may also have been thinking about this Saturday’s Put it to the People March, which promises to be somewhat larger, as hundreds of thousands take to the streets of London to demand the final say on any Brexit deal.

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Whatever the reason, as one of those gearing up even now to protest in public, I’d like to answer Shipman. First, it’s not like we haven’t been writing to MPs. Our campaign has sent hundreds of thousands of letters, postcards and emails to our elected representatives in the past few months, expressing dismay at the mind-numbing crisis that Brexit has become. These are important. But bulging postbags and cluttered inboxes alone don’t change history.

Saturday’s march will once again allow new and marginalised voices to be heard. And when the dust settles, it’ll be the hundreds of thousands who took to the streets to fight for change who will be remembered.

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In recent years marches have fallen short of securing policy change on our nation’s defining questions. They have, however, left a permanent mark on the politicians who ignored them. I was too young to attend the Iraq protests. But I know their effect on those in power at the time and how much harder it would ever be for a government to go to war again in defiance of such public resistance. Today’s politicians ignore us at their peril.

Saturday’s march differs from others in the past because Brexit is not a done deal. The government has stalled, and politics is at a standstill. We march days before our country could crash out of the European Union altogether. Public outrage at the crippling incompetence and indecision in Westminster reached new levels this week when the petition to revoke article 50 and remain in the EU hit 2m signatures, crashing the parliamentary petition website several times. But this crisis must be ended with the public’s consent – and Saturday’s march is another important opportunity to give a voice to this country on the defining issue of our age.

Theresa May’s deal may be voted on again next week, the prime minister hoping that the threat of a no-deal crashout coaxes rebels back into line. Yet MPs still haven’t decided what Brexit means. May’s deal will leave millions of people asking, “What’s the point?”; and no deal will raise the question, “What’s the price?”

We’re facing a crunch week – though the EU has agreed to an extended Brexit deadline of 22 May if the prime minister’s deal is passed, and 12 April if it is not – and reasonable MPs must surely conclude that the only way out of this mess is to put some version of it back to the people. We know any Brexit will damage our futures and leave us poorer. We know that allowing May’s deal over the line will only lead to more years of painful negotiations and bitter arguments. All the while, the chance to tackle issues of climate change and cybersecurity – which my generation are determined to do – will fall by the wayside as our country obsesses further over a disastrous project.

The vast majority of young people opposed Brexit in 2016, and even more of us oppose it now. Nearly 2 million young people have come of voting age since June 2016. Three-quarters of them want to remain in the European Union, and many of them will be among us on Saturday demanding their say on an issue that will define their futures.

When the Brexit deal is so far from what was promised three years ago, and when the costs of Brexit are clear for all to see, we should not have to stand by and allow this government to force through a deal that nobody voted for. Saturday’s protest could not be better timed. It is a chance for all of us to force our politicians to listen, while we still can.

• Lara Spirit is co-president of Our Future Our Choice