WE do truly live in the age of the vacuous slogan. Some, in the likes of the advertising industry, are harmless enough. Others are dangerous.

While we should by now be inured to Boris Johnson and his bizarre Brexit odyssey, a newspaper picture of the Prime Minister delivering a speech, showing his “Unleash Britain’s Potential” slogan not once but three times, caught the eye. It flagged just how important Mr Johnson and those around him believe their slogans are (even though they mean nothing).

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Most people, you would imagine, would be able to recite the three words, championed by Mr Johnson and his adviser, Dominic Cummings, which precede the “unleash” bit. More is the pity. For anyone who has been blissfully unaware of the sorry mantra of this Conservative election campaign, the three words are “Get Brexit Done”.

The “Unleash Britain’s Potential” is of course entirely at odds with virtually all economic projections, including the forecasts of the Conservative Government under Theresa May.

In the context of their understanding of the phrase “unleash potential”, Messrs Johnson and Cummings might want to take a look at accountancy firm PricewaterhouseCoopers’ latest economic outlook, published this week.

PwC predicts UK growth of 1.2 per cent this year, way below the long-term annual average. Scottish growth is projected to be slightly ahead of this, at 1.3%, but this is cold comfort, as the whole of the UK is laid low by the Tory Brexit foolishness.

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Very many economists have flagged the drag on the UK economy from worries over Brexit, which are weighing down business investment and have sent net immigration from other European Union countries to the UK tumbling, before we get to the actual departure from the EU.

Messrs Johnson and Cummings now want to “Get Brexit Done” by January 31, having thankfully failed in their previous drive to bring it about by Hallowe’en.

Growth in Scotland and the UK as a whole is projected by PwC to slow to just one per cent in 2020, with risks weighted to the downside, assuming an orderly exit.

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And we should remember 2020 is a period in which the UK, even should Mr Johnson get his way, would still be protected from full Brexit realities by transition arrangements agreed between Mrs May’s administration and the EU.

It is after these post-Brexit transition arrangements, when the UK is exposed to the cold realities of actually leaving the European single market and losing crucial free movement of labour and frictionless trade, that the truths of this folly will hit home for many.

Sadly, it would be likely to take many people until then to realise that the ideological Brexit being pursued by Mr Johnson and his acolytes comes at a cost.

The Conservatives’ manifesto has set yet another arbitrary deadline, this time of being out of the transition period at the end of 2020. You would imagine, on Mr Johnson’s past record, this will be a “no matter what”-type of stubbornness.

There seems to be a view on the part of the Conservatives that a future trade deal with the EU would be negotiated in this timescale. It is easy to understand why many actual experts are warning that this is unrealistic, on the basis of how long trade deals usually take, and the latest hidebound timescale declaration from the Tories has rekindled worries of a no-deal departure. These worries are justified, especially if Mr Johnson gets the kind of majority that would stop Parliament from keeping a firm rein on him.

Hope remains that Mr Johnson might fall short of his desired “working majority” and so be thwarted in his ambition to ram his hard Brexit through Parliament.

However, there is a danger that his sloganeering, which implies no cost and big benefits from Brexit, is appealing to people. This is alarming, and surely somewhat baffling given the Brexiters’ abject failure in the nearly three-and-a-half years since the June 2016 referendum to show any convincing benefit at all.

The problem, as Messrs Johnson and Cummings probably know fine well, is that some people are fatigued from hearing about Brexit. This is a sorry state of affairs. And given the intensity of the drive by Mr Johnson and his ilk to try to get Brexit through by painting a picture that it is just something to tick off the list before moving on, you can see why some people might be beguiled by this propaganda.

Anything is possible. The Leave campaign managed in 2016 to persuade people blighted by years of Tory austerity that the fault lay at the door of the EU. That was truly incredible, although perhaps no more jaw-dropping than traditional Labour voters supporting a Conservative leader with a right-wing agenda because they want to “Get Brexit Done”.

Maybe some voters think they will be able to stop thinking about Brexit once it is done. Sadly for them, the end of the transition period is actually when they will really have to start thinking about Brexit. Living standards will be hit as growth is hammered by leaving the single market.

We should bear in mind that, under Mrs May, the Conservative Government’s own forecasts showed economic damage for every single Brexit scenario relative to staying in the EU. The least-damaging of the Brexit scenarios would be remaining in the single market. Surprise, surprise.

The UK is already paying the price for the plunge in net immigration from the EU since the Brexit vote, which has hit its ability to reach its potential in terms of availability of labour and skills. This situation will get a whole lot worse if the Tories achieve their aim of clamping down on immigration by ending free movement. This would give those who backed Mr Johnson on Brexit belated food for thought as living standards were hit.

Then there is the likely loss of frictionless trade if Mr Johnson has his way. The Society of Motor Manufacturers and Traders warned this week that UK annual car production would drop by one-third to one million vehicles by 2024 if Brexit leads to tariffs with the EU, with output lost to other countries.

People would also likely have to deal with erosion of employment rights under a Tory government that did not have to adhere to the EU’s socially desirable labour laws. Sadly for the currently fatigued, and everyone else, there would be oh-so-much to ponder on the Brexit front at that stage.