AT long last. For one glorious afternoon, the SNP’s Westminster contingent quit playing the Westminster game and stopped being stuck in the corner, silenced, tamed and ignored.

The party’s Westminster leader, Ian Blackford, repeatedly refused to sit down after the Speaker turned down his request for a new debate about Brexit’s impact on devolved governments during Prime Minister’s Questions.

Struggling to keep control of the chamber, Bercow red-carded Blackford and barred him from the Commons for the rest of the day. Then the entire contingent of SNP MPs marched out of the chamber, to sarcastic cheers of “Bye!” from the government benches.

John Bercow scolded the exiting MPs like naughty children – “Now you don’t have the chance to ask your questions” – and the next Tory MP called to speak quipped: “With the amount of people leaving it feels like one of my after dinner speeches.

Guffaw, guffaw.

So what was achieved? Actually, quite a lot. Despite predictable Labour criticisms that the gesture was childish and counterproductive, any rational onlooker would have to concede that the SNP have been patient beyond reason since the Scots’ decisive Remain vote.

Nicola Sturgeon was the first politician to tackle the Brexit crisis constructively by producing a paper in December 2016, outlining a way for Scotland (and Northern Ireland) to remain in the single market as the majority of their voters demanded. That, of course, was ignored and mocked – even though the British Government is now presenting mash-ups of those SNP ideas. The Scottish Government also decided to take Theresa May at her word when she talked about treating the Holyrood, Stormont and Cardiff governments as equals. SNP MPs played it by the book, turning up at midnight, speaking to an empty Commons chamber and waiting, waiting, waiting for the “Mother of Parliaments” to let the democratically elected representatives of Britain’s second biggest nation have their say.

We all knew it would never happen. But it was important for Scots to witness the truth. The SNP’s reward for abiding by Westminster rules since 2014 has been to suffer the coldest of cold shoulders. By contrast, yesterday’s mass walkout – the SNP’s first since Alex Salmond’s dramatic masterstroke in 1988 – garnered immediate and unprecedented publicity plus a speedy response from the grudging Scotland Office. It is surely shocking, that the only way to be taken seriously south of the border is to appear ready to break all the rules.

Indeed the surprise and borderline contempt in media interviews with Ian Blackford after the walkout demonstrated exactly why it had been necessary. Despite being the third largest party by MPs and second largest by membership in the whole UK, despite having the largest Remain vote of any parliament or assembly, despite receiving a series of false Tory promises about a debate – first in the Commons, then (without SNP input) in the unelected House of Lords, then in Tuesday’s final Commons debate – despite all of this, London-based political commentators were still astonished and even sneering at the SNP walkout.

Bizarrely, believed this “inexplicable” action had come out of the blue. How on earth could any serious political observer fail to see the frustration of Scots MPs, the repeated, broken promises by the UK Government and the growing lack of parity between Scotland and Northern Ireland over the same Westminster “one size fits all” Brexit? The only explanation for missing that long build up of anger and frustration is that the media outside Scotland doesn’t actually care. Earlier this week 19 minutes of Brexit debate was “devoted” to devolved issues, with just one man called to speak -- the Chancellor of the Duchy of Lancaster, David Lidington. In case no-one fae sooth realises, he represents Aylesbury not Aberdeen. Did no-one think that was even a wee bit wrong?

The National:

The walk-out has wrong-footed Scottish opposition parties too – parties which supported the Continuity Bill and rejected the UK Withdrawal Bill’s power grab have condemned the SNP’s “grievance” politics without offering any alternative strategies.

But amongst independence supporters, the dramatic action has also whetted the appetite for more.

Clearly, SNP MPs believed their point was made within hours and quickly returned to work, confident they’d made an impact. They did. By 5pm yesterday the SNP had gained over a thousand new members and David Mundell had been forced to promise a statement on the devolved assemblies and parliaments today. He says that was always scheduled – clearly, it wasn’t.

But with results like this, should the SNP MPs have stayed out? Parallels have been drawn with the Irish situation, where Sinn Fein fights elections but doesn’t take seats at Westminster. Tempting though it is to follow their example (and I’m sure the prospect has crossed the mind of every SNP member since their first forlorn trips south in 2015), the SNP has adopted a different, incremental strategy.

It might be right, it might be wrong. It might arise from our dogged if sometimes infuriating tendency to be law-abiding at all times, or the knowledge that half the population is yet to be convinced about the merits of independence and could easily believe that a slackening of effort in the Commons constituted a dereliction of duty.

Interestingly, though there is another precedent – a walkout by Donald Dewar, back in the days when Scottish Labour actually led the push for devolved powers instead of screeching from the margins. Dewar, as Shadow Scottish Secretary led a walkout of Scottish Labour MPs from the Commons soon after the 1987 election, apparently prompted by Scottish Labour MPs proposing that they quit Westminster altogether and decamp to Edinburgh.

That would have been quite a gesture – remember at the time there was no Scottish Parliament so Westminster was the only source of all legislation affecting Scots. The impatience of his MPs, and the walkout probably forced Dewar to participate in the Scottish Constitutional Convention, which at the time (and 30 years later) was an unusual experiment in British politics. Labour sat down with rival political parties, the churches, trade unions and representatives of civic Scotland to create the blueprint for a Scottish parliament. The SNP, for the most part, sat it out.

I wonder if there is a lesson in there for Nicola Sturgeon now.

What else needs to happen in Scotland as a result of her MPs’ short but effective disturbance of the force at Westminster? Surely, it’s time to re-awake the Constitutional Convention and reconvene its members – along with new groups who back Holyrood’s stand against Westminster’s power grab?

It may seem like a thankless and politically pointless task as Labour and the LibDems wax hot and cold about the importance of defending their own devolution settlement. But you can only defend democracy with more democracy.

This could be the moment to encourage all progressive Scots of every party and none to put their shoulders to the wheel and work together. What’s to lose in the face of a Tory party that’s determined to steam-roller their undemocratic power-grab through, whether there’s a debate about the devolved parliaments or not?

Having spent the week in Reykjavik, making the second #Nation film, it’s clear the bold Icelanders wouldn’t tolerate Westminster’s collective insult to their national identity for a nano-second. To quote Katrin Oddsdottir, a lawyer and member of the team behind Iceland’s crowd-sourced constitution; “Courage is not like other things. You don’t get brave by talking about it. You can’t learn courage. You get courageous by being courageous.”

She’s right. SNP MPs have begun the business of learning not to be side-lined by anyone – be that the Tory Government or perhaps the leadership of their own party. That’s an important moment.

As the Vikings used to say, and the modern Nordic nations still believe, “Fortune favours the bold.” It’s a lesson Scots are finally learning.