It is a great relief to know that though the British Establishment may be unforgivably slow in recognising the obvious, it isn’t absolutely incapable of it. Last week the powers that be – the forces of conventional wisdom and political correctness – finally saw the light on immigration. They didn’t exactly admit it, of course. They merely stood by quietly and allowed others to tell the truth about immigration, without trying to shame them into silence. In its quiet way it was a remarkable cultural moment – a national tipping point.

On Monday a cross-parliamentary group led by Frank Field, the former Labour minister, called for a limit to immigration. There were no howls of outrage, merely a few squeaks. In a report called Balanced Migration, accompanied by a poll by YouGov, the parliamentary campaigners made the obvious point, accompanied by painstakingly gathered facts, that immigration cannot continue at its present uncontrolled rate. The country cannot stand it. At current levels, (mostly immigration from outside the European Union) 7m people will come to live here by 2031; that is the equivalent of seven cities the size of Birmingham. By now only bigots against the truth deny the pressure that recent immigration imposes on schools, hospitals, prisons, housing and infrastructure.

All this ought to have been obvious long ago. It’s what the vast majority here think. What’s new is that it’s possible to say so without being accused of playing the race card or the numbers game; I’m not sure why, but it must have something to do with the fact that many ethnic minority people now think so too. The YouGov poll showed that 85% of all people think immigration is putting too much pressure on public services, 76% that Britain is overcrowded and 81% that the government should greatly reduce immigration to Britain. Sixty per cent of Asians and 45% of blacks think the same, so such thoughts are not necessarily racist; ironically, it is their agreement that has made discussion possible.

The Balanced Migration group is calling for a stop to net immigration: it proposes that the number of immigrants (from outside the EU) who are given permission to settle here should be kept to roughly the same as the number of British citizens who are emigrating. This wouldn’t affect temporary work permits or family reunion, but it would significantly cut the population explosion here.

Part of the point of this launch is the usual invitation to a national debate. I have a couple of suggestions to offer. One of the many standard arguments in favour of immigration is that we need the workers. Even if immigrants make a net contribution of only a few pounds a year (62p a week, according to the exhaustive House of Lords economics committee investigation this year into the economic impact of immigration) or even if they are a large net cost, we’d be lost without them because they do essential work. They do all the care work, the unskilled work and the seasonal work. Who else would do it?

The answer is simple. There are already plenty of British citizens here to do it. I don’t mean the unemployed Britons here, though some of them might be suitable as well. I mean two other groups. One consists of state sector workers. The Labour government, while in office, has created well over 800,000 public sector jobs, most of them unnecessary. Not only is this make-work, it is make-waste. All those functionaries do not merely sit at desks, consuming heat and light and waiting for their pension. They create other costs and other work. Such is the mindless power of bureaucracy that one outreach worker with an absurd brief such as advising Irish people in Birmingham about sex (I didn’t make that one up) can call upon new initiatives, new meetings, new groups, new funding, new employees and more expense. Meanwhile the old and the lonely are neglected, unless a Filipino or a Somali immigrant can be found for them.

This vast army of state sector workers should be redeployed. They should be allowed to keep their job security, salaries and pensions, but they should become social care workers. They should, in person, look after the old, the sick, the mentally ill and the displaced; we are all capable of social care – looking after a bedridden pensioner, or feeding a sick child in hospital, giving a worn-out carer a respite break, working in a women’s shelter, or advising a desperate family about debt. We don’t have enough citizens doing this. It is supremely valuable work, far more so than checking the ethnicity of people parking cars.

This important work is not exactly skilled, but it is responsible and demanding. It is not right to give this work to low-paid, poorly educated immigrants who speak little English, when we have plenty of people here already who could do it.

Similarly with work that is more obviously unskilled, or low-skilled, like looking after parks and streets and countless other essential jobs, we need not depend so heavily on immigrants when we have huge numbers of citizens who could do it, yet they are often denied the opportunity. I mean people with learning disabilities.

Learning disability is an awkward term. It has nothing to do with mental illness. It means a significant intellectual impairment, or – crudely – a low IQ. Clearly a person with a mild or moderate learning disability couldn’t usually expect to do a skilled job. But for many doing an unskilled job can be a great joy, a source of pride and independence, as well as useful to all concerned, whether it’s stacking shelves in a friendly supermarket, assisting a park keeper, working on a building site, in a hotel laundry or picking strawberries. And according to government estimates, between 580,000 and 1.75m people here have mild to moderate learning disabilities; that is a huge source of willing workers. Yet despite the known wishes of people with such disabilities, despite the pressure of various lobby groups on their behalf, they find it difficult to get jobs.

Immigrants have brought great things to this country. One of them, rather oddly and recently, is the opportunity at last to talk more openly as a society about the costs and benefits of immigration, without being denounced as a heartless xenophobe or closet racist. Enoch Powell is at last being proved wrong.

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