For a couple of hours on Friday morning, for the first time ever, I felt old. At the age of 65 (nearly 66!), I am old, but I’ve never actually felt old.

All it took were a few clips of Farage, Johnson and Gove, plus interviews with the likes of Liam Fox and Neil Hamilton (exhumed from his political grave as Mr UKIP in Wales) for my spirit to start shrivelling inside me.

It wasn’t so much that the Remain campaign had lost (and by quite a big margin, whatever some are now arguing), though I was certainly feeling the pain of that, particularly for my fellow campaigners in We Are Europe, who’d put their hearts and souls into persuading their peer group to get themselves registered, get inspired by Europe, and vote IN.

It was more a cumulative despair at what the campaign as a whole had revealed about the state of our democracy. About the depths of disaffection with ‘the political class’ in the Westminster bubble in particular. About the yawning gaps between London and the rest of the country, between young and old, between rich and poor.

About the apparent inability on the part of any progressive pro-European to find an authentic way of responding to people’s deep concerns about immigration. About the demonization of ‘the Other’ recklessly let loose, despite knowing how hard it will be to contain it.

About how it took a cruel and senseless murder to bring people to their senses in terms of the way they pursued their campaign. About Project Fear vs Project Hate as the best (apparently) we had to offer voters for reasons to vote one way or the other.

About the bitterness, the invective, the endless lies. About the literally untouchable influence of a handful of neo-liberal media barons, insouciantly sacrificing the interests of the least well off in this country to reinforce their own ideological power base.

Against that backdrop, despair, briefly, seemed the only option. It felt as if every single one of the difficulties we already faced in making sustainability central to the UK’s future destiny had been multiplied tenfold – overnight! Think about those challenges:

• Addressing climate change with the urgency it now demands – with this lot running the show?!
• Redistributing the wealth of this country more equitably – with this lot?!
• Being part of a growing international movement trying to rebalance the global economy and protect human rights – with this lot?!
• Combatting crass nationalism and hateful xenophobia – with this lot?!

You get my drift. That was Friday. Today, as I write, it is Sunday. And in the intervening period, hope has crept back in, borne along on a constant flow of forward-looking commentaries, mutual support, dogged resolution, and a quality of anger informed (in Martin Luther King’s words) by ‘the hope of redemption’.

It’s not the first time for me that the incandescent coals of anger have seen off the shades of despair! What has happened through this Referendum campaign is just so wicked, with millions of people gulled into taking out their (wholly understandable) anger at the failure of our mainstream parties on the EU – the very institution that has done more than any other part of our political system to protect their rights and interests.

And it’s such an appalling outcome for young people – 73% of 18- to 24-year-olds voted for Remain. They’re left now contemplating a much more precarious future for themselves in an intolerant, divided and isolationist country that speaks to few of their values and even fewer of their hopes and aspirations.

It’s these young people who will be paying the highest price for David Cameron’s countless political misjudgements – not least his decision that the franchise for the Referendum should not be extended to 16 and 17-year-olds, on the grounds that this would create ‘an unwelcome precedent’! At least he can now reflect at his leisure on what those 16- and 17-year-olds might have done to offset the inadequacies of his wretched campaign.

Two things are now already beginning to emerge from the confusion of a lost battle. First, there is now little hope for this country other than in the growing political awareness and passion of young people to help build a better world – tolerant, inclusive, fair and sustainable – not just here in the UK, but globally.

In that regard, our We Are Europe campaign was for me a ‘revelation in practice’. I’ve often acknowledged, theoretically, the ability and readiness of young people to transform our moribund political institutions and structures. But I’ve never been party to any political initiative where I witnessed this for myself, in practice, through a campaign growing in confidence and punching harder day-by-day.

It was perfectly clear to me, by polling day, that if the forlornly predictable Stronger In organisation had let our lot loose, properly resourced, from the start of the campaign, there might have been a very different result.

And might that not have been the case, by the way, if they’d chosen to use Caroline Lucas a whole lot more to help front the campaign? Her little film (see embed, below) about why Europe matters so much to all of us here in the UK – both from an historical and a future perspective – was very inspiring, and a wonderfully fitting tribute to the death of Jo Cox.

Second, it’s pretty clear to me now, at this time of unprecedented political instability, that the answer to those sustainability challenges lie not in any one party (not even in the Green Party) but in the millions of people in all parties and in no party who can see that it’s game-over for today’s failed and heartless political and economic orthodoxies. Including the two main political parties that are still mindlessly in thrall to those orthodoxies.

People have been talking about some kind of ‘progressive alliance’ ever since the 2010 General Election. If ever there was a moment where such an alliance could start coming together, and start working out a game plan to transform our political prospects between now and 2020, this has to be it.

As Jeanette Winterson said in yesterday’s Guardian: “Everything starts as a story we tell ourselves about ourselves. Every political movement begins as a counter-narrative to an existing narrative.”

I’m not quite sure what that means for me personally – but I sure as hell need to find out before I get any older!

Jonathon Porritt is Founder Director of Forum for the Future. His latest book, ‘The World We Made‘ is available from Phaidon.