Stephen Crabb is Secretary of State for Wales and MP for Preseli Pembrokeshire. Ruth Davidson is Leader of the Scottish Conservative and Unionist Party, and an MSP for Glasgow.

We both came into politics for the same reason – to break down Britain’s class barriers and build a society where opportunity is open to all.

Our upbringing may have been hundreds of miles apart, but it had much in common – strong women raising us to believe that with hard work we could be whoever we wanted to be. In houses where nothing came for free, we were taught the value of service, application and industry. That we were better than no-one and no-one was better than us.

Fundamentally, this is what drew us to the Conservative Party; to build a stronger society where it no longer matters where where you come from, what street you grew up on, what kind of family background you have, or what your parents did for a living.  A Party that asked “What does the Conservative Party offer a working class kid from Brixton? They made him Prime Minister.”

Brixton may have been a world away from the communities in which we grew up – in Wales and Scotland – but the message that it doesn’t matter where you come from, but what you do, resonated strongly. In our parts of the world, it was the Labour Party which tried to claim this mantle of progress. But, for us, Labour looked to the past and spoke to the past, seeking only to ensure the ideological battles of the 1980s created more division and bitterness.

Far from creating progress, it was a vehicle of protest and divisiveness with powerful party machines that controlled some of the most vulnerable communities at a neighbourhood level. It wasn’t just the services you could access that Labour sought to control, but issues as fundamental as which house you could live in or which school your children were sent to. It was a suffocating, stultifying big-government approach to controlling lives and snuffing out the spark of individuals.

Thirty years on, Labour is once again looking backwards to resurrect some of these ghosts.

But, as Conservatives, our mission and purpose in this new century remains steadfast- to extend opportunity, to foster aspiration and ambition, and build strong communities and families in which the most vulnerable are protected. Labour might believe in government – but we believe in people. This is our One Nation vision.

For some, One Nation conservatism represents some woolly, wetter, weaker brand of conservatism; more consensual; less hard headed. It’s a soundbite or – worse – a catch-all, nebulous concept to dull criticism but which doesn’t really mean anything by itself.

It’s not. One Nation is about the muscular projection of our values of fairness and opportunity. It’s about British values of fair play, Conservative values of helping up those in need while clearing the way for people to explore new horizons. It’s about making sure people can take their own decisions, giving them freedom, choice and leaving more money in their pockets so they can make the choices about their familes needs rather than the state taking decisions on their behalf without their consent.

In the kind of political street fights we have both been through in Scotland and Wales, we know that you can’t get away with any weak and wooly brand of politics. You have to be passionate. Your head screwed on, yes, but also with a full beating heart.

It is precisely because of our upbringing that we are Conservatives, not in spite of it. The desire, the passion, the need to fight for a future where our communities and our country empowers people to do the best they can is what pumps the blood through our veins. And, more than that, it to reward people who strike out and try to build a better life for themselves and their families – not to upbraid them for it. It is about helping to pick up someone who’s tried, but failed, encouraging them to knock the dust off and try again. It is about telling every child that their future is limited only by their own ambitions.

That’s what Labour doesn’t understand. When Ed Miliband tried to claim the Conservative One Nation mantle, his party critics turned on him.  The Labour MP Paul Flynn declared: “What the xxxx does it mean?… It doesn’t mean a thing does it?”

Actually it does. And it’s pretty plain. One Nation speaks of unity. It speaks of the thousand spider-trails of interactions that makes this country work, and makes it a place half the globe looks to with envy.

A One Nation government speaks to all parts of the United Kingdom, recognising the distinctiveness and diversity of the family of nations that comprise the Union, but fundamentally affirming the Union as the most successful political and economic union the world has ever known.

But One Nation also speaks to the kind of society we want, one based on aspiration and opportunity, compassion. It is a potent ideal which has permeated through our politics for more than a century.

It rejects the politics of nationalism which seeks to pit one part of our nation against the other. It asks us to take a more complex but more enriching journey; one that embraces difference and recognises that in diversity lies strength.

We now must deliver that message more than ever – against a nationalism that wants to believe our differences are irreconcilable, and an extreme left-wing ideology which would only make our decline irreversible.

In both Scotland and Wales, there was a time when socialism stood for self-help, community strength and empowerment through education. Our towns and cities are filled with the legacy of their efforts, from the magnificent libraries and memorial halls built in South Wales valleys, to the splendour of Glasgow’s People’s Palace. The tragedy of socialism is that in the post-war era it became an ideology of welfarism and indebtedness.

We believe that it is our One Nation Conservatism which must now find a new way to enrich the present just as an older, better socialism once helped the past; by building homes for those who want a foot on the property ladder, by reforming schools so that the poorest children have the same chance as the richest, and by creating a welfare state that promotes work for those who can, and comes to the aid of those who can’t

Some call this Blue Collar Conservativism, Modern Conservatism… we know it just as conservatism. In both Scotland and Wales, it is a an ageless idea whose turn has come.