AND so, after three chaotic years, Boris Johnson has finally left the despatch box. His parting quote from Terminator 2 hinted at a mad dream of one day returning to prove his critics wrong.

Like that other circus-sized ego, Alex Salmond, he couldn’t bear the thought of quitting the limelight entirely so left the door ajar to a comeback.

But while Tory MPs cheered him from the Commons chambers, the public has already moved rapidly on. There will be no vigils for Boris. No marches down Whitehall. Unlike Arnold Schwarzenegger, he won’t be back.

Mr Johnson claimed with typical unreliability that his mission had been “largely accomplished”. But history will note that a Prime Minister who started with an 80-seat majority and immense goodwill - at least in England - compulsively squandered it and inspired his party to mutiny.

More Custer than Churchill, he fancied himself a great commander, but was shot by his own troops, the most ignominious end of them all. 

Sir Keir Starmer exposed his true legacy at PMQs yesterday simply by reading out what his would-be successors are saying about his Government’s multiple failures. The PM has left the Tories a toxic inheritance of strife, division and a reputation for serial incompetence.

But one small corner of Scotland still appears to keep a flame burning for the great Leaver.

The Scottish Government unit producing the new part-work prospectus for independence appears to be paying homage to Mr Johnson’s Brexit campaign by producing documents that say almost nothing about what lies on the far side of a vote for change.

As a ‘scene setter’, the first instalment of Building a Better Scotland could be forgiven for its lack of tangibles, as it contrasted Scotland’s economic and social metrics with those of 10 similarly sized nations in and around Europe, without saying what an independent Scotland would actually do to emulate them. 

But the second part has continued the eerily blank theme. In her foreword, Nicola Sturgeon says the papers are intended to “help people make an informed choice about their future”.

But on the basis of what information exactly?

Despite the First Minister’s repeated criticism of the Brexit campaign of 2016 failing to spell out what a Leave vote would mean in practice, her own prospectus is equally vague. There’s not enough to trouble the side of a bus.

Instead, ‘Renewing Democracy through Independence’ spends around 40 pages listing Westminster’s many flaws and disappointments, while implying that democracy under independence would somehow revert to its pristine, Edenic state. 

Some of the document is idiotic. “Only 9% of MPs in the House of Commons are elected by the people of Scotland. While this broadly reflects Scotland’s population share, it does not reflect a status for Scotland as one of four equal nations within the UK,” it complains.

So what would reflect that status? Is the Scottish Government suggesting England, Scotland, Wales and Northern Ireland should each have a quarter of our MPs? If so, Northern Ireland would go from 18 seats to around 162, with some 7,600 electors in each one. While England would keep just 30 per cent of its 533 seats, with almost 240,000 electors in each one. Drivel. 

The paper’s overarching complaint is that Westminster has too much power and can do what it wants despite devolution, ignoring Scotland and riding roughshod over Holyrood.

There is a sense of horror that a parliamentary majority in the Commons can make, modify or repeal laws at will. But there is nothing to say why the parliament of an independent Scotland would be any more restrained - towards local government, for instance - or wiser in its decision-making.  

The White Paper of 2013 at least put forward plans.

It said a written constitution would be “central” to protecting people’s rights and would be drafted by a constitutional convention. The new paper merely says a written constitution is an option, and makes no mention of a constitutional convention to bring it about.

Nor is there anything on how local government would be treated. The White Paper backed “subsidiarity and local decision making”. The new paper is silent on Scotland’s other tier of elected government.

There are gaps galore. In the “renewed democracy” of independence, who would be head of state, for instance? The White Paper said an independent Scotland would remain a constitutional monarchy. The new paper doesn’t broach the subject at all.

Ms Sturgeon says independence would mean Scotland rejoining the EU. But her readers aren’t told whether it would do so with a Prime Minister, President, royal or other figurehead out front.

It’s just as much of a pig in a poke as Brexit.

Small wonder Professor James Michell of Edinburgh University, an expert on the SNP and its history, was scathing about the latest part of the prospectus earlier this week.

Writing in Holyrood magazine, he called it a “dismal, negative, inspiring document” that suggests the SNP would “recreate a warped and discredited form of democracy, an independent Scotland that would simply be a little Britain”. 

Perhaps we shouldn't even call it a prospectus, as there’s nothing to hold the proposers to account on. Like the Leave campaign, it’s ripe with things to get you annoyed, but there’s nothing specific about the alternative.

Democracy would, we’re invited to infer, simply be better and nicer after a Yes vote, as Westminster would be out of the picture.  

While that may be so, it isn’t assured. Democracy is inherently messy.

“The worst form of government except for all the others,” as Churchill said.

As well as historically impressive figures, it throws up rogues and embarrassments such as Mr Johnson. 

An independent Holyrood could be enlightening, or it could bring out the worst in the SNP’s secretiveness. Repeal of freedom of information, anyone? As the New York politician Gideon J Tucker once observed: “No man’s life, liberty, or property are safe while the legislature is in session.” 

Independence might or might not improve our democratic realm.

It would plainly be wrong to think our democracy would automatically be worse than Westminster, but also to think it would be automatically better.

The new paper’s lazy appeal to Scottish exceptionalism is not a good sign.

Of course, we may get more detail as the series goes on.

But right now it is urging voters to back independence on a blank slate, something which could give a future government a troubling amount of power. That should worry every democrat.