Night lights in Europe (Photo credit: Wikipedia)

In 1914, on the eve of the First World War, the British foreign secretary Sir Edward Grey looked out of his window at the street lamps being lit, and said “The lamps are going out all over Europe, we shall not see them lit again in our lifetime”.

Now, on the eve of the Brexit referendum, I fear the lights may be about to start going out again in Europe — and this time the first place to fall dark will be Britain.

The European Union was built on a dream. Not a dream of common markets or free trade, but a dream that the children of those who fought the most calamitous wars in history could sit down together and share a continent in peace and goodwill. That they could share their resources and face their challenges together. A brotherhood of man. And it has worked: after centuries of war, the most blood-soaked continent in human history has enjoyed 70 years of peace.

You are holding that dream in your hands when you go to cast your vote. Take care you do not crush it. You are holding your children’s future, their chance to live in a continent at peace. Do not throw it away for a slogan and a piece of tattered flag.

We’ve heard a lot from the Leave camp about taking our country back, but I fear I am losing mine. My Britain is not a place that would turn its back on its friends and allies in their hour of need. Vladimir Putin’s tanks are menacing the borders of Eastern Europe, his planes are invading our shared airspace. The mad killers of Isis are plotting new ways to kill us. This is no time for running away.

This is London calling. Generations brought up on the Clash song perhaps do not know that the phrase goes back further. It was how the Second World War broadcasts from London to occupied Europe living under Nazi tyranny began. For generations of Europeans, that was what Britain meant: the country that did not desert them in their hour of need. On Friday London will be calling again, but what will its message be?

In the last few days, I have seen friends who have lived in Britain for more than a decade, who have British nationality and whose children were born in Britain told they are not British enough to have an opinion on Brexit. Alan Sugar, the celebrity businessman, has said Gisela Stuart has no right to an opinion because she was born in Germany, although she is a British citizen, a British member of parliament, and has lived in Britain for 42 years — longer than I have been alive. It doesn’t matter which side she’s on. My Britain is not a place where some citizens are more British than others, or where we have to submit to Alan Sugar’s race test.

I have watched as Nigel Farage unveiled a campaign poster that was almost a perfect copy of Nazi propaganda, that depicted the hungry and broken masses fleeing the burning cities of Syria as a threat to us. My Britain is not a place that deserts the needy and the desperate, or that is afraid of people because of their religion or the colour of their skin.

My Britain is not a place where a young woman MP is gunned down in the streets by a man who declared “Death to traitors”. It is the man who shot Jo Cox who is the traitor to my Britain. His name will soon be forgotten, while hers will outlive us all.

My Britain is not a place that blames its problems on immigrants. The politicians have been lying to you, and not just Farage. It is not the fault of the immigrants who work hard and pay their taxes that the government has not spent those taxes on building houses, on providing school places, on more GPs, on the NHS.

Nor are any of these things the fault of the European Union. A generation of British politicians have told you to blame immigrants and the EU for their own failure to address the problems of our country. That is classic scapegoat politics. It is always easier to blame some one else, and if you manage to convince enough people, you can ride their fury all the way to power.

But what happens when you get your way and it turns out leaving the EU or stopping the immigrants doesn’t solve the country’s problems? When there still aren’t enough jobs, or enough doctors? You’re going to need some one else to blame, and that’s what keeps me awake at night. Who will be the next scapegoat when Brexit fails to solve our problems? Second generation immigrants? British Muslims? People whose accents Alan Sugar doesn’t like?

In these final days of the campaign, it has struck me that Boris Johnson was the perfect leader for the Brexit campaign. A man who, to judge by his own public utterances, didn’t even believe in leaving the European Union until it happened to fit his personal ambitions. A man who doesn’t mind tearing his party apart to get the keys to Number 10.

That’s what Brexit is: turning our backs on our beliefs and our values, abandoning our friends and allies, for a little short-term political expediency. And it won’t even work: the experts are united that it will be an economic disaster.

This is London calling, but what’s the message in 2016? For more than 70 years, the international image of Britain has been one forged in the fires of 1940. Whatever out differences, the rest of the world has looked on us as a country that can be trusted, when it really matters, to do the right thing. If we vote to leave, I fear Britain will be something quite different in the eyes of the world: the country that cut and ran, the country that abandoned its allies, selfish and treacherous.

That is what you are holding in your hands when you cast your vote, but more than that you are holding hopes and dreams. We all of us walk in one another’s dreams, every day, but on Thursday you will carry with you to the polling booth the hopes and dreams of a continent, of 500 million people, of your children and of children yet unborn.  Do not abandon them. It is an awesome responsibility. Do not let the lights go out over Europe.

Okay, that’s all. It’s up to you.