18 September 2014. It is a date that we in Scotland have been talking about for years, and it will be etched in our nation’s memory for generations to come. I look forward to telling my grandchildren about it, with pride and passion for everything that Scotland has achieved.
Because one month today I am voting to stand in solidarity with working people right across these islands. I am voting "no thanks" to Scotland walking away from our friends and neighbours across the United Kingdom.
The United Kingdom is a country shaped by shared values – not least tolerance, fairness and internationalism – to which all nations and communities can contribute and from which all learn.
It is grounded in values of cooperation and solidarity between countries and nations that make us all stronger.
What we gain economically from working together rather than walking away is underpinned by something far more powerful - the gains from the interaction and cross fertilisation of ideas and experiences – out of which comes shared values and the desirability of shared decision making.
It is not simply that a working family in Paisley has more in common with a working family in Preston or Ebbur Vale than with the Duke of Sutherland. It is that in their shared endeavour and common experience we all gain.
What the UK teaches us – not least through the intermarriage, intermingling and immigration with Britain over the centuries – is to see the world though someone else’s eyes.
The UK embodies a quintessentially modern idea I hold very dearly. We are enlarged by people who are different from us. We are not threatened by them.
I believe deeply that change is needed on both sides of the border – and beyond our borders.
Right across the UK, Tory economic policy and welfare cuts make many fearful and force choices between heating and eating for still more. The SNP's council tax freeze is taking money from the poorest communities while forcing cuts to the public services they need most.
The nationalists rely on rekindling an outdated sense of victimhood. Wales, Northern Ireland and great cities like Liverpool, Newcastle and Manchester find no place amidst a cultural conceit that holds that everyone south of the Tweed is an austerity-loving Tory.
The nationalists say – walk away and all will be well. Yet while the clear majority of Scots want change, we do not judge independence as the route to achieve those changes.
As Labour campaigners, our belief is that when we see injustice we stand and fight to change it, and so we must be the voice for the change that most Scots want.
The ideal and the practice of solidarity is what most challenges the nationalist notion that somehow Scotland needs independence because Scots are better at being fairer than the English, or at least, would be without the English around.
At a deeper moral level, walking away is not and never can be an act of, or the basis for, solidarity.
At our best, Labour has been the party of constitutional, economic and social renewal – the party of Scottish home rule. We established the Scottish Parliament. But for us that parliament, with whatever powers it now has and will have in the future, is a means to an end. And that end is to improve the lot of working people and ensuring no one is left behind.
That task is still best achieved working alongside our comrades in the rest of the UK. As the old trade union slogan has it, “In Unity is Strength”.
The independent Institute of Fiscal Studies has estimated that an independent Scotland would have to impose £6bn of cuts or tax rises after a yes vote over and above those already planned. That is more than Scotland spends on schools, more than the entire budget for pensions and equivalent to half the current NHS budget.
The truth is that separation means cuts. What Alex Salmond is asking Scotland to vote for is Austerity Plus for decades to come.
That is what makes his pitch to Labour voters that there would be fewer cuts and more wealth redistribution in a separate Scotland so cynical.
If you take a moment to look beneath Alex Salmond’s rhetoric at his actual record, there isn’t much to back up his claim to want redistribution. In seven years as First Minister there has been not one policy which redistributes wealth from rich to poor – indeed the opposite is true.
But the certainty is that the financial chaos that would be inflicted by the nationalists' confusion over the currency of a separate Scotland would lead to more cuts and greater poverty.
This currency chaos would hit the poor harder than anyone. The cuts would have to be across the board – from schools to hospitals, from pensions to welfare payments to some of our most vulnerable fellow citizens.
My starting point is that I want Scotland to be fairer, more prosperous and have greater opportunities.
That’s why I have come to the conclusion that we are more likely to have the strength to become fairer, more prosperous and have greater opportunities by working with our neighbours in the United Kingdom.
For the nationalists the starting point is the desire to leave the United Kingdom. The question of Scotland being fairer, more prosperous and having more opportunity is secondary to their core belief.
In the closing weeks of this campaign we are offering Labour voters what most Scots see as the best of both worlds: more decisions taken by Scots here in Scotland, backed up by the strength, stability and security of the UK.
When I campaign in towns and cities across the country, I speak to people facing the same challenges as my own constituents in Renfrewshire. And I meet dedicated Labour campaigners focused on fighting to improve their communities.
I believe that if Scotland walks away from the UK, breaking up our Labour family, it would be a blow to the cause of social justice across the United Kingdom.
When my grandchildren ask what I did in the referendum, I want to be able to say that I worked and campaigned for a principled and pragmatic solidarity that shares risks, rewards and resources across these islands.
In this final month before polling day, my call to Labour supporters - wherever you live in the UK - is come and work with us in these closing weeks of the campaign.
Join us in upholding the ideal and the practice of solidarity in these islands. We'll give you a warm welcome because we understand ' unity is strength' as we campaign for victory on September 18th.
While the referendum is a decision for us in Scotland to make, the debate about solidarity and social justice is one for across the UK.
Let’s stand together in solidarity on September 18th, both as a Labour movement as a the family of nations that is the United Kingdom.
Douglas Alexander is Labour MP for Paisley and Renfrewshire South and shadow foreign secretary