What constitutes objective reality? It appears that this most intractable of questions – first posed by Plato 2,500 years ago – has a simple answer. It is whatever the UK Government deems it to be, by passing an emergency bill.

So, at the stroke of a legislative pen, Rishi Sunak is able to determine that Rwanda – a single party dictatorship, where most of the mass media is state owned and controlled; where street children, homeless people and beggars are routinely rounded up; where political opponents are allegedly tortured in safe houses and military bases; and where refugees are disappeared, killed, and arrested in suspicious circumstances – is a safe environment for asylum seekers to Britain.

This despite the fact that the Court of Appeal ruled, following extensive research and investigation, that it could not conclude the country was safe.

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Perhaps if I made a large enough donation to the Conservative party, the Prime Minister would agree to introduce emergency legislation stating that I am a talented concert pianist with a large fortune and the sexual magnetism of Chris Hemsworth.

With small boat crossings on the English Channel, the UK Government has managed to synthesise, in a single issue, everything that is wrong with our politics.

Its handling of the problem demonstrates, emphatically, the extent to which our politicians overpromise and underdeliver, in order to get elected and stay in office, leading to disappointment and resentment when they inevitably fail.

For, if one thing is abundantly clear, it is that they will fail to stop tens of thousands of people making their way to this country to settle every year, even if they ever do manage to fly a few hundred of them to central Africa.

The problem for Tory ministers is not just that the thousands of desperate souls piling onto dinghies on French beaches don’t read the Daily Mail and the Spectator, it is that they are driven by social, economic, climatical, and geopolitical forces bigger, stronger, more diverse, and profound than our politicians are willing to admit and address.

Halting the ongoing, irresistible movement of populations north and west in the coming decades will require long-term, inter-governmental co-operation and investment on a colossal scale and our politicians, whose horizons generally extend no further than the next election, have neither the vision, imagination nor, frankly, the ambition to tackle it.

Instead, they tinker around the edges with disingenuous short-termism, playing whack-a-mole with the latest immigration issue du jour.

Today, it is small boat crossings, before that it was taking back control of our borders from EU migrants; before that it was the Sangatte ‘jungle'; going all the way back to the 1970s when immigrants from former British imperial territories were seen as the greatest threat to this country’s traditional way of life.

The Herald: Migrants land in Kent in AugustMigrants land in Kent in August (Image: free)

There is no likelihood that Labour will behave any differently in office, because they too overstate their power and ability to effect genuine change on this, or any other issue for that matter.

In the past century, only four prime ministers have made an appreciable difference to the lives of most people – Churchill, Attlee, Thatcher, and Blair – five, if you include Cameron but he did so by accident via Brexit, so he doesn’t count.

The rest were simply managers, minding the shop until they were despatched by voters to spend more time with the overblown advances for their memoirs.

The truth is that beyond building new schools and hospitals and paying for more police officers, governments are constrained in what they can do by institutions, such as the civil service, and convention.

The success or failure of the economy, for example, has little to do with the actions of politicians. They can create a fiscal environment that is receptive to private enterprise and offer companies incentives to locate, expand and generate employment, but they have to balance that with likely receipts and competition from abroad.

The only time they have a real impact on the economy is when they screw-up spectacularly such as Black Wednesday – when Britain crashed out of the European Exchange Rate Mechanism – or the Kwarteng budget.

Politicians of all mainstream parties tacitly agree that they should operate within a narrow set of common principles – the rule of law, the independence of the central bank, a mixed economy with minimal state interference in the operation of free markets, and with Labour and the Conservatives alternating in office to maintain a nominal appearance of democracy in action.

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Such an arrangement ensures economic stability and social cohesion but it also gives rise to anger and frustration at bus-ticket, Tweedle Dum and Tweedle Dee politics.

When there is so much to agree upon, so many institutional and constitutional constraints, and so few instruments and mechanisms to effect genuine change, it’s not surprising that politicians should resort to exaggeration and pretension about the scope of their influence and abilities.

On the positive side, the system’s natural gravitational pull towards moderation and consensus acts as a brake on fanatical politicians, such as Suella Braverman, who don’t recognise their limitations and are seduced into believing their own press.

Her favoured way of dealing with the small boats issue – withdrawing the UK from all of its international agreements on human rights and refugees – would run into countless barriers, not least of which is English Common Law which protects people from being placed in danger by the government or any of its agencies.

For all of Sunak’s rhetoric about preventing foreign courts interfering with British sovereignty, it is safeguards built into the UK’s own laws and conventions that are likely to frustrate his Rwanda plan.

If he was ever tempted to go down the Braverman route, by taking the UK out of the European Convention on Human Rights and the UN’s Refugee Convention, it would send a clear message to countries like Russia and Turkey, which frequently face adverse rulings at the European Court in Strasbourg, that this country lacks confidence in the ECHR system.

Leaving the Convention could also leave British subjects in a weaker position against the state if their rights were breached.

It would be ironic if the Conservative party, whose lawyers played a key role in drafting the ECHR and which has historically defended individual rights against an overly dominant state, was to be responsible for its decline.

Sunak may believe he can change the facts simply by legislating new ones into existence, but he is likely to find it as difficult as I would knocking out anything more complicated than Chopsticks on the ivories.