By John McKee, Commentator and freelance journalist

MHAIRI Black came out the other day declaring her disgust with the White Paper which Alex Salmond produced in 2014 as a blueprint for independence. I was on the other side, but I think I know how she feels. The campaign I fought for, Better Together, rather failed to set the heather alight. Coming to symbolise a sclerotic establishment, the No campaign looked too much like the defence of power for the people who are used to running things. A more positive vision was needed, desperately.

I sat behind Gordon Brown as he delivered his barnstorming speech at the final Better Together rally. It struck a chord. Under Mr Brown and the auspices of the then Daily Record editor Murray Foote, an appeal was made to the majority of Scots who said in poll after poll they wanted neither to stand still nor to depart the UK, but to opt for a more radical devolutionary settlement. A “Vow” was made to the Scottish people and the Unionist party leaders signed this promissory note.

It promised more powers over tax and welfare and ensured a continuation of Barnett formula funding. It was a wide-ranging, ambitious gambit which captured the public’s imagination at the fever-pitch crescendo of the Referendum campaign. The Union may have been saved on September 18, 2014, but any failure to deliver on the deal would surely plunge the country back into constitutional hurly burly.

And yet, David Cameron blundered. On the very morning of a victory that had been delivered to him by Mr Brown, the man he had ousted from Downing Street, Mr Cameron squandered all capital and tied Scottish devolution to English Votes for English Laws. Mr Brown had urged him that morning not do so but, with the sort of cavalier self-confidence of an Oxbridge PPEist who understands politics in the abstract, Mr Cameron ignored him. Like on Brexit, he offered red meat for the backbench wolves on the Tory Right so they did not eat him. Of course, his premiership was eventually devoured nonetheless.

Mr Cameron’s manoeuvring led to cries of betrayal. It has become an axiom in Nationalist parlance that the Vow was a trick and a lie.

But this line no longer bears scrutiny. This very week, those promised powers have been delivered as the new income tax powers come into effect. The Scottish Government has set in place tax bands differing from England, whilst Jeane Freeman sets up the new Scottish Benefits Agency. The terms of the Vow have now been met. The Union has kept its promise.

No longer will Holyrood be able to pass the buck on austerity to London, or to complain (legitimately) about the inhumane cuts to welfare when it has the power to top up those benefits.

When Scotland wanted devolution, it was delivered. When it wanted Devo Max too that was delivered. When it demanded a say on the very future of the Union, this was acquiesced.

It is now time for Scotland’s nascent Parliament to mature. Accountability for tax and spend will force easy grievance narratives from the debate. The Labour Leader, Richard Leonard already talks of a wealth tax and Ruth Davidson proposes cutting tax.

Nationalists, like Unionists, are spread across the spectrum from left to right and now that fundamental questions of revenue and spending are not mere political hockey to lob at London’s net, the SNP face questions which may split the iron consensus which has prevailed in the Salmond-Sturgeon era.

We’re not playing hockey any more, its shinty now; and the bruises may hurt the independence movement, but they will toughen our democracy