CANVASSING in Tranent, Prestonpans and Wallyford in East Lothian, I come across elderly former miners. Not so many these days, to be sure. More often you meet their widows. Mining was a killer job, destroying your lungs and breaking your back. All that is left now in Scotland is the National Mining Museum and memories of an industry and a workforce that were integral to our national culture.

I’ve been angry with the Tories during this election campaign. They are, after all, planning a total meltdown of the welfare state. However, I was more irked than angry listening to Kezia Dugdale on the radio, as she explained to listeners on the BBC that SNP members are not “progressives”. Actually, I quite like Kezia. But she was only three years old when the great 1984 miners’ strike took place – the defining confrontation between Thatcherism and the British (and Scottish) working class.

During that historic strike, and for a number of years afterwards, I was an economic adviser to the Scottish Area of the National Union of Mineworkers (NUM), providing the statistical ammunition to keep individual pits from being shut down and thousands of miners being thrown on the scrapheap. So I don’t take well to being lectured about my lack of “progressive” credentials.

In the 1980s, I set up and ran an outfit called the Scottish Coal Project. We were a small group of academic researchers dedicated to defending the Scottish coal industry and its workforce from the predatory attacks of the Thatcherite government. My chief colleague was Richard Saville, son of the late, great left-wing historian John Saville, a close collaborator of Ralph Miliband, father of Labour’s Ed and David Miliband. One of our research assistants was a certain John Swinney – I gave him his first job. Fancy: the SNP is so “un-progressive” that John Swinney was working to defend the Scottish miners from Thatcher more than 30 years ago!

On the doorsteps, I’ve been reminiscing with East Lothian miners about the great 1984-85 strike and its aftermath. The strike is not yet relegated to history. Thatcher used military-style tactics to break the NUM and so neuter trade union defence of living standards ever since. The background to the dispute is too complex to detail here. Suffice to say, Arthur Scargill, the NUM leader, launched the strike without proper democratic consultation with the union’s membership. He also walked into a trap, because Thatcher had been stockpiling coal, the better to wait the miners out – a fact that many of the union’s advisers, including Richard Saville and myself, tried to tell him. But Mr Scargill rarely listened to advice.

The upshot was that the miners were crushed politically by Thatcher, with many being sent to jail. The circumstances of these arrests and prosecutions remain of doubtful legality. Suspiciously, in Scotland the conviction rate for striking miners was three times higher than in England. In particular, picketing at the Ravenscraig steel plant in Lanarkshire resulted in 292 arrests in one day. Of course, tempers were short and I am not condoning violence. But this number of arrests looks excessive. In any event, it is time that we held a public inquiry into these convictions – north and south of the Border – so that justice can finally be seen to be done.

Calling for such an inquiry is not a slur on the police, who these days bravely face the horror of dealing with terrorism on our streets. Mrs Thatcher was happy to militarise a civilian police force for political ends during the miners’ strike, branding the NUM “the enemy within”. No-one blames ordinary cops caught up in this transparent political manoeuvre.

Kezia Dugdale’s ridiculous claim that the movement for self-determination in Scotland is not “progressive” hardly stands the test of history. We can start with former miner Keir Hardie, founder of the Scottish and then UK Labour parties, and an early champion of genuine Scottish home rule – by which he meant complete self-determination within a family of British nations, like Canada or Australia. In 2015, I put down an early day motion in Parliament to mark the centenary of the Hardie’s death. The motion ended by expressing its hope that “Hardie’s lifelong support for Scottish home rule, universal social justice and equal rights for women will yet bear fruit.” The majority of signatories were from the SNP.

Only 10 Labour MPs bothered to sign, but they included leading Corbyn supporter Richard Burgon.

Then there is James Maxton, leader of the Independent Labour Party (ILP) which honourably split from the official UK Labour Party in 1932, after Prime Minister Ramsay Macdonald entered a coalition agreement with the Tories to implement massive austerity. The history of the Labour right siding with the Tories is hardly a new thing. Maxton’s ILP was resolutely in favour of Scottish home rule, again meaning Scotland would determine its own taxes and spending. ILP-ers introduced repeated Scottish home rule bills at Westminster. Meanwhile, the official Labour Party became ever more centralising, finally rejecting all support for Scottish home rule till the rise of the SNP in the 1970s forced an opportunist change of policy.

My point is that home rule and radicalism have been synonymous in Scotland since the 19th century. When official Labour step away from supporting Scottish self-determination, it is precisely in order to move to the right on social and economic matters.

The call for Scottish self-determination has always been about creating the domestic political machinery necessary to implement radical social and economic reform here in Scotland.

Home rule agitation began in the late 19th century, linked to land reform and the demand to break up the great landed estates. The home rule cause was taken up by the early workers movement anxious to eradicate poverty and poor housing conditions in Scotland’s urban conurbations. Faced with the intransigence of the Labour right (with its preference for enjoying the trappings of the imperial British state) the radical wing of the home rule movement shifted during the brutal Thatcher years to demanding complete Scottish independence – the better to ensure social and economic justice. Witness the breakaway in 1976 from official Labour by Jim Sillars, after right-wing Labour MPs deliberately sabotaged the first devolution legislation. Nothing Scottish Labour have done in recent years convinces me the leopard has changed its spots, whether it was the Better Together campaign prioritising a Tory UK over a social democratic Scotland, or the covert and not so covert deals being done between Labour and Tory councillors.

Kezia Dugdale has done what she could to oppose Jeremy Corbyn and the re-radicalisation of Labour in England. Minutes after Corbyn defeated Owen Smith for the Labour leadership, she said: “I don’t think Jeremy can unite our party and lead us into government. I’m not changing that view. It’s very clear. It’s written down.”

If the Tories win on Thursday, only a strong SNP contingent at Westminster has a chance to protect Scotland from falling off the Brexit cliff edge. Why am I so sure? Because the SNP is the genuine continuation of the long radical and progressive tradition in Scotland.