TODAY is the third anniversary of the greatest British act of self-harm since the Suez debacle of 1956 when the British state was given a painful lesson in what happens when you think you are still a global superpower but you no longer have the clout to back up your delusions of omnipotence.

Sadly, Britain dismally failed to learn that lesson because, 64 years later, it harrumphed its way out of the European Union on the back of a delusional belief that Britain could still be a global player in its own right.

As we all know, Scotland opposed the decision to leave the EU. Despite that, and despite the claims of the Better Together parties in 2014 that the UK was a partnership of equal nations, Scotland was given no say in the form that Brexit was to take, and the concerns of the Scottish Government were routinely ignored.

To add insult to injury, the Conservatives have used that Brexit which Scotland did not vote for as an excuse to undermine and bypass the devolution settlement which Scotland did vote for, and moreover have done so without even pretending to seek a mandate from the people of Scotland to tamper with the powers of the Scottish Parliament.

By any metric, Brexit has been a dismal failure. Scottish Government Constitution Secretary Angus Robertson has pointed to research that suggests Scotland's public services have been deprived of £3.2 billion in tax revenues directly because of Brexit.

In another small example of the harm caused by Brexit, Eurostar announced today that it deliberately runs trains to Paris and Brussels with empty seats due to the additional time it takes for passport and immigration checks to be carried out, a necessity imposed by Brexit.

In their Anglo-British supremacist arrogance, the advocates of Brexit imagined that Brexit would only affect foreign nationals arriving in the UK – the “controlling our borders” rhetoric. It did not seem to occur to them that Brexit would also entail greater checks and restrictions on British passport holders travelling to Europe.

Meanwhile, both Labour and the Conservatives are maintaining a conspiracy of silence about the negative impact of Brexit, which also ensures that the British media remains reluctant to mention the downsides of Brexit.

On today's lunchtime news on the BBC, the headline story was about how the British economy is uniquely forecast to shrink this year. The only major economy forecast to do so. All other countries face the exact same global pressures that the UK does, yet their economies are forecast to grow. Yet the B word was not mentioned in BBC news coverage of the story. It's hardly surprising that regret about Brexit is now widespread among former Leave supporters. An opinion poll published this week found that in all but three constituencies in the UK, most people agree with the statement that "Britain was wrong to leave the EU".

Across the UK as a whole, 54% agree that Britain was wrong to leave the EU, 18% neither agree nor disagree and only 28% disagree. In Scotland, the belief that Britain was wrong to leave the EU is even more marked.

Other polling suggests that in a referendum about EU membership, 57% of people in the UK would vote to rejoin the EU. A recent poll in Scotland found that in a rerun of the EU referendum, 72% would vote to remain, while 69% would vote to rejoin the EU given the chance.

Of course, both the Conservative and Labour parties are determined not to give them a chance. There is only one way back into the EU for Scotland and that is as an independent nation which becomes a member of the EU in its own right.

Even prominent Conservative supporters are now speaking out to admit the obvious – that Brexit was a dreadful mistake. Speaking to BBC Radio 4's Today show, the financier and Conservative donor Guy Hands, the founder, chair and chief investment officer of the private equity firm Terra Firma, said Brexit has “been a complete disaster” and added that the claims made about Brexit by Leave campaigners were a “bunch of complete and total lies”.

The tragedy for those in the UK who regret Brexit and who wish that the UK would rejoin the EU is that even in the unlikely event that the two main British parties were to offer them the chance of another vote on EU membership, the EU would be highly reluctant to allow the UK back in unless support for membership was overwhelming and there was a clear sign that Britain had mended its exceptionalist ways and would be a co-operative team player in future.

Even then, the UK could kiss goodbye to its precious rebates and opt-outs. EU membership for the UK would certainly involve signing up to the single currency and membership of the Schengen Zone. That's a humiliation that English nationalists would find too hard to swallow.

On the other hand, a Scottish application to join the EU as an independent nation would meet with considerable goodwill and sympathy from the rest of Europe. There is widespread public awareness in Europe that Scotland is considerably more pro-European than the rest of the UK, which would boost a future Scottish application for membership.

This piece is an extract from today’s REAL Scottish Politics newsletter, which is emailed out at 7pm every weekday with a round-up of the day's top stories and exclusive analysis from the Wee Ginger Dug.

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