The small boats carrying migrants will be tracked across the channel.  When these step onto British soil – doing so illegally – they will be met by the armed forces.  They may be screened and sent to Rwanda which will be paid for taking them.  Once they have arrived there, they won’t be able to apply for asylum here.

Such is the picture that the Government is painting of the scheme announced yesterday.  To say that it provokes a long list of questions would be an understatement.

Such as: is it really the role of the armed forces to act as a police force?  Just how many and what proportion of arrivals will be sent?  How much will the scheme cost taxpayers – including that of the Greek-style reception centres in which some arrivals will apparently be held here, and where and how many of these will there be?

In practice, will the arrivals dodge the authorities, not claim asylum, and vanish into the wider population?  Above all: will the plan really work as a deterrent, and survive the coming blitz of human rights-based legal actions?

This mass of questions comes from both the Left and the Right.  The Left’s critique is based on the claim that the scheme is both cruel and useless – a critique less punishing than it may sound, since if the plan is the second it can’t really be the first.  The Right’s boils down to the second.  The cry is: “we’ve heard it all before”.

To make a fair judgement, it is essential to understand what the scheme actually is and isn’t.  It is not, repeat not, offshoring – an Australian-style scheme in which people apply for asylum from abroad.

At its core is the separation of people into legal and illegal streams, under the terms of the Nationality and Borders Bill, which is currently passing through Parliament.  Those entering illegally once removed abroad will not be allowed to apply for asylum here at all.

In short, the scheme is not primarily aimed at asylum seekers as a whole.  Nor even at all those who will be entering the country illegally once the Bill becomes law.

It is targeting a relatively new and potentially destabilising crime racket – the small boats phenomenon – which sees unscrupulous gangmasters paid to organise a potentially deadly journey.  Remember the 27 people who drowned outside Calais last December.

Boris Johnson argued yesterday that this parallel illegal migration system is deeply unfair to those who arrive legally – not to mention all those who voted to take back control of our borders.  This is incontrovertible.

And any accurate judgement on the scheme will understand the context correctly.  The Prime Minister’s critics argue that this is the first time that a British Government will refuse sanctuary to a mass of people most of whom are found by the authorities to be genuine refugees – evidence of extremism, even of fascism.

The Government will claim in the courts that it is obliged to ensure that refugees are sheltered – but not necessarily that they are sheltered here in Britain.

Whatever you may think of the legal arguments, the political realities are unarguable.  First and foremost among them is an open secret that neither Ministers nor their critics want to acknowledge: namely, that this is the most immigration-friendly Government in recent history, stretching all the way back to New Labour.

Johnson has junked the net target for controlling immigration numbers, going instead for his beloved “Australian-style points-based system“.

There is now no annual limit on semi-skilled work permits; qualification requirements and the salary threshold has been lowered; an unlimited number of foreign students can stay on for up to two years; the obligation to first advertise jobs in the UK has been dropped.

Pre-pandemic, Brexit was seeing a boom in net non-EU migration: it rose to 282,000 by the end of 2019 – the highest level ever recorded.  The year to March 2020 showed an overall net migration figure of 313,000.

Then there are the other refugee schemes.  The Government’s opponents will raise its stuttering scheme for Ukrainians.  Its supporters can counter with its offer of refuge to up to three million Hong Kongers.  Where is the racism there?

An accurate representation of the Government shows not a cartoon of wicked monsters imposing a nazi regime – or even of ruthless strategists set on trapping Labour –  but a snapshot of desperate politicians at their wits’ end.

For the fact is that the number of asylum applications from small boats rose from 2,012 in 2020 to 23,000 by November last year.  Where is the upper limit?  The evidence suggests that, even taking the closure of other routes into account, the gangmasters have stumbled across a revolutionary discovery.

Namely, that it isn’t at all hard to sail a small boat full of people seeking a new life in Britain from the long Normandy coastline, regardless of the stance of whatever government holds power in France.

Yes, France – which when I last looked was a liberal western democracy.  And that’s the point: the small boats aren’t sailing to Britain from Tartus in Syria, say; or from Karachi, full of Afghans who have somehow got there.  They’re coming from a European country that is already a safe haven.

The Government’s scheme may not work.  But it is only reasonable to ask its critics the question: what would you do, then?

I exclude from their list the ridiculous Yvette Cooper, whose opportunistic party has no answers, and which gave us when in government the spectacle of illegal immigrants cleaning the then Home Secretary’s office.

There are two alternatives – one coherent, one not.  The former is to give away control to the gangmasters rather than taking it back ourselves: stand back, shrug shoulders, and let events take their course.  Whatever changes there may be in migration polling, the voters wouldn’t stand it for a moment.

A British Marine Le Pen would be on 25 per cent of the vote.  Or more.  And how could such a policy remotely be proclaimed as fair?

Then there is letting people apply for asylum from abroad.  That might stop the small boats were the number of potential migrants to remain roughly as at present (though I doubt it).  But there were 84 million refugees worldwide in 2020. And they are far from being the only people potentially eligible to claim.

Obviously, only a proportion of the whole number would opt to come to Britain if given the option of claiming asylum at a British Embassy.  But the fact is that there is no upper limit on the number we would be obliged to take.

Like other governments, ours is struggling with worldwide obligations shaped three quarters of a century ago, and which are now hopelessly out of date.

Which is why Johnson and company should be cut a bit of slack on the Rwanda plan (which is not unlike the EU’s deal with Turkey over migration in 2016, as it happens).

Priti Patel is wrestling with a Home Office dysfunctional at best and mutinous at worst.  And Downing Street was paralysed over the issue last year.  It looks as though the arrival of Steve Barclay as Chief of Staff, representing a new reliance by Johnson on Conservative MPs, has swung the balance.

But now this policy has been announced, it must be effected.  The real struggle will surely be not with Tory critics, whose numbers have been small, but with the courts – and with a mass of obligations in urgent need of ovehaul.