From the application of human rights laws to the analysis of statistics, immigration can be a complex subject, and the public debate about it can be deeply dishonest. But most of us ought to be able to agree some common-sense principles.

From bringing skills and enterprise to adding to the cultural capital of the country, immigration can bring great benefits, but in large numbers can also bring great challenges – so the flows must be controlled. This control needs clear laws, strong enforcement and tough but intelligent border security. Decisions ought to be made not in the interests of foreign nationals, immigration lawyers or supranational organisations, but the British people. And the decision-makers themselves must be politicians, directly accountable to those who elect them.

There is of course huge scope for disagreement in the practical implementation of these principles. We can differ over the extent of the need for foreign workers, for example, when there is a dire lack of technical and vocational education and training for people already living here. We can argue about the desirability of allowing colleges and universities the right to sell long-term immigration, not just education, to hundreds of thousands of foreign students.

Regardless of such differences, it is difficult to deny that our immigration system is failing, despite Brexit and the end of free-movement rules.

We are yet to see meaningful post-Brexit immigration statistics. In 2020, thanks to the pandemic, net migration fell by 88 per cent to just 34,000. In 2019, net migration was 271,000 – high, but not unusual for the past couple of decades, when the number has been known to exceed 300,000. We can already see from the number of visas issued that immigration is about to soar again, probably to record highs.

Comparing 2021 to 2019, work visas (239,987) are up 25 per cent, family visas (280,776) are up 49 per cent, and student visas (432,279) are up 52 per cent. More than a quarter of foreign students are Chinese, but the number of Nigerian students is up 415 per cent, Pakistani up 256 per cent and Indian up 164 per cent.

This enormous increase in immigration is not happening by chance. Even as the Government ended European free-movement rules after Brexit – a decision driven, pollsters agree, by concerns about sovereignty, democratic control and immigration – Boris Johnson demanded a more liberal policy.

Work permits were unlimited, and the definition of “skilled work” was watered down. The shortage-occupation list was extended to allow the recruitment of foreign workers in yet more trades. Employers were no longer compelled to seek workers from the resident population before recruiting from overseas. A salary threshold, supposedly set to ensure only high-skilled immigration, was set at £25,600 and for some workers only £20,400. Foreign students – whatever their qualification – were given the right to stay and work in Britain at the end of their courses.

And a new framework was established. The points-based system, the Government likes to point out, is inspired by the Australian model, which focus groups tell them is widely believed to be tough. But while Australia is uncompromising on illegal immigration, its policy on legal migrants has been liberal for decades, with its per capita immigration higher even than ours. Just as Australia’s points-based system was created to increase immigration, so is the British one. Our numbers will keep going up.

A points-based system surrenders the very principle of control. When migrants want to come to Britain, if they have the requisite number of points they simply win the right to come. And the principle of control – the very promise of Brexit, remember – will be further eroded by trade deals the Prime Minister is negotiating. In India last week, Johnson signalled his agreement with further liberalisation for Indian workers and claimed, despite probable record immigration this year, “we’re short to the tune of hundreds of thousands [of workers] in our economy”.

This is not true. But then, of course, the debate about immigration has never been honest. Advocates of mass immigration pretend we have always been “a country of immigrants” and engage in countless forms of evasion and sophistry. Some say the numbers are irrelevant and all that matters is control. Others insist that the public simply want the system to work, even as they oppose every reform to make it work. Most common, however, is those who pay lip service to the notion of overall control, while opposing control in every visa route going. In practice, they claim that each application is of vital national interest.

It is easy to make it sound reassuring. Who could reasonably oppose skilled workers coming here to contribute? But under the points-based system, skilled workers are not only astrophysicists: they might also be bricklayers. Who could oppose the brightest and the best coming to use their talents here? But the majority of foreign students attend institutions outside the Russell Group of top universities. Three quarters of the increase in student visas from 2019 comes from applicants to lower quality universities. All have the right to work here afterwards, whatever their qualification and whatever their job.

Supporters of mass immigration might not care. Every day that these policies continue, they get what they want and conclude that they will win in the end. But nobody has ever made the argument for such rapid population change and won an election. And this includes the Prime Minister, who has no mandate for the policies he is pursuing. His manifesto promised “overall numbers will come down … we will ensure that the British people are always in control”.

The British people have good reasons for wishing to remain in control. They know, from bitter experience, the costs of mass immigration. They know the problems caused by rapid social change, stark cultural divides, pressure on infrastructure and public services, housing shortages and high rents, job displacement and the suppression of wages.

When they realise, having voted to take back control, that the PM has given it away, the Tories will find there will be hell to pay.