The look of wide-eyed, guilty panic in the eyes of Boris Johnston and Michael Gove on Friday morning hinted at what was later confirmed: the Brexiteers who had schemed for this moment all their political lives had absolutely no plan for life after Thursday.

But those of us who argued passionately that Britain should remain in Europe should also concede that there is little consensus among progressives now Britain has voted “out” – either how we will improve the lives of those who felt so left behind that they voted to Leave, or to build a winning coalition to rescue disadvantaged people from the clutches of right-wing escapism.

The Conservative Party has just crashed the economy, left Britain more alone than at any point I can ever remember, and betrayed the hopes of a generation – and while the national emergency grows, our governing party is pre-occupied with who is going to bag what job. Yet progressives must recognise that the reason we could face an early general election is because the Tories still think they can win one, despite putting a bomb under their much-vaunted reputation for economic competence.

And the basis for that frankly sickening Tory confidence is clear. Jeremy Corbyn is a decent man, but he never even enjoyed the confidence of Labour MPs to lose.

David Cameron: There is no doubt about the result

I fought a positive campaign, working with others, setting out an optimistic, open vision of Britain. But sometimes Labour seemed keener to give a bloody nose to David Cameron than to keep us in Europe, even though membership of the European Union is way more important.

For a Liberal Democrat, this is visceral. I am an internationalist, who believes we must work across borders to face the great challenges such as the world’s largest ever movement of people, climate change, the rising power of multi-nationals and terrorism, along with the arrival in the international labour market of a billion Chinese workers which has depressed wages across the western world. A progressive political settlement needs international co-operation, and it has been the EU that has guaranteed worker rights, consumer protection and environmental safeguards.

But if you are a progressive, pro-European who recognises that you need a successful economy to deliver social justice, I just don’t see a future for you in Labour. Even if Labour MPs achieve their “Jexit”, might not Labour members simply elect someone equally extreme – leaving the path clear for a Tory Party to beat up on the poor?

And this makes me furious. The IPPR has shown that the poorest will be hit twice as hard as the richest by new inflation caused by sterling’s slide. The pound is at its lowest in 30 years. There is now a £900bn hole in the pension funds.

Low-paid workers are worried sick today about their jobs, with Tata Steel now at risk. Some leftists might enjoy seeing trading in banks being temporarily suspended, but the reduction in the value of the state’s share in RBS has already cost taxpayers £7.3bn. And as with the last recession, it will be the poorest who pay.

But there is a rallying point for progressives who refuse to settle for a future of glowering across the White Cliffs of Dover. That rallying point is the Liberal Democrats. Since I announced that we would go into the next election as the only party calling for Britain to remain in the EU, thousands have joined our party, at the rate of one a minute.

By yesterday, almost 7,000 had joined, and the number's rising.

We must be the voice of those who see a positive future in Europe. Young people – 73 per cent of whom voted to Remain – are determined to keep opportunities to travel, work and study abroad. More than that, these new members want to demonstrate that Britain remains an internationalist, open and optimistic country.

But as a progressive I am just as concerned about the 52 per cent who voted to leave. Many, understandably, feel marginalised, with stagnating wages, insufficient training to gain better jobs, a housing shortage and struggling NHS. Ironically, the vote was less a rejection of Europe as a rejection of a Westminster that seems disinterested in the problems of people it purports to represent.

It is the disadvantaged whose modest living standards face a further assault thanks to “Brex-trick”.

My number one priority has always been to transform education and training, better housing and healthcare to give real life chances. The British are naturally welcoming, and many concerns that have been attributed to immigration are actually about the disgraceful lack of opportunity to move into better jobs, to get a house, or a school space for your child. These are challenges that I am determined to fight for.

Liberalism is about championing the individual against the powerful. That means standing firm for our Human Rights Act, against internet surveillance and illiberal extremism orders. But it’s also about protecting individuals from those giant evils that rob people of their freedom: poverty, poor housing and inequality. This is my pitch – to centrist and centre-left voters.

I believe in four core principles. Freedom – the right of people to live as they see fit; the second is democracy – a state that supports freedom has to be democratic, with power dispersed, which is why we fought to democratise Europe.

Brexit reactions – in pictures Show all 10 1 /10 Brexit reactions – in pictures Brexit reactions – in pictures Supporters of the Stronger In campaign look at their phones after hearing results in the EU referendum at London's Royal Festival Hall AP Brexit reactions – in pictures Leave supporters cheer results at a Leave.eu party after polling stations closed in the Referendum on the European Union in London Reuters Brexit reactions – in pictures Mr Cameron announces his resignation to supporters Getty Brexit reactions – in pictures Donald Tusk proposes that the 27 remaining EU member states ‘start a wider reflection on the future of our union’ Getty Brexit reactions – in pictures Ukip leader Nigel Farage greets his supporters on College Green in Westminster, after Britain voted to leave the European Union PA Brexit reactions – in pictures Supporters of the Stronger In Campaign react as referendum results are announced today Getty Brexit reactions – in pictures Boris Johnson leaves his home today to discover a crowd of waiting journalists and police officers Getty Brexit reactions – in pictures Leave EU supporters celebrate as they watch the British EU Referendum results being televised at Millbank Tower in London Rex Brexit reactions – in pictures Supporters of the Stronger In Campaign react as results of the EU referendum are announced at the Royal Festival Hall Reuters Brexit reactions – in pictures Supporters of the Stronger In campaign react after hearing results in the EU referendum at London's Royal Festival Hall PA

Our third core value is fairness, whether it be how police deal with young people on the streets or the way jobcentres treat benefits claimants. Fairness is not only right in itself, it leads to people working better together.

Our fourth core value is environmentalism. Climate change, pollution and the degradation of the natural world pose one of the biggest threats. We have to act at home and internationally to promote green technologies, producing clean energy and transport, stopping the waste of natural resources and energy and protecting nature.

If you are a green voter, a labour voter or a moderate Tory my appeal to you is this: these are causes that should speak to anyone who calls themselves progressive.

But amazingly, it is only the Liberal Democrats fighting for them. Britain, and its most vulnerable people, need you to join me in the fightback.