One of the UK’s key economic advantages is its success at attracting skilled immigrants. In particular, the ability of London to generate the wealth that Britain depends on to finance its public services is inextricably linked to the city’s openness to ideas, capital and immigrants. But Britain’s immigration debate is now all about how to make it harder for newcomers rather than making the country more attractive to them. To a large extent, this is being driven by the concerns and fears of suburban and rural voters, especially older ones. The readiness of politicians from across the political spectrum to pander to these fears is damaging the economy, feeding euroscepticism and with it the possibility of the UK quitting the EU.

The government wants to reduce net immigration to less than 100,000 a year. To this end it has tightened up the regime for student visas and for skilled immigration into the UK from outside the EU (non-EU countries account for two-thirds of the net immigration: the EU the remainder). There is little the government can do about EU immigrants, which explains the increasingly hysterical campaign to reduce their access to benefits. The government argues that the scale of immigration is prejudicing the employment prospects of lower-skilled British workers (over the last year more than half of new jobs went to immigrants, and youth unemployment is at a record high, ergo they are taking British jobs); placing a further burden on an already overwhelmed National Health Service (NHS) and school system; and leading to abuse of the country’s welfare system.

These claims are either wrong or misleading. Net immigration into the UK is not particularly high. It certainly rose following the opening up of the UK labour market to the new eastern European members of the EU in 2004. Over the 8 years to 2011 net immigration averaged 214,000 a year, before falling to 165,000 in 2012. In the context of a country as populous as the UK, this is a relatively modest inflow – adding about 0.3 per cent to population each year. And it is not especially high in a European context: over the last ten years, net immigration in Britain has been higher than France and Germany, but lower than in Italy or Spain. Talk of ‘mass immigration’ is well wide of the mark.

The UK is also very good at attracting skilled immigrants: almost 40 per cent of first generation immigrants have a university degree; the comparable figures for France and Germany are half that, and even lower for Spain and Italy. Indeed, the south-east of England is home to the biggest concentration of foreign professionals anywhere on earth. The reasons for this success range from the English language to the greater readiness of UK employers to recognise foreign qualifications. Many other first generation immigrants have vocational qualifications in skills like construction, which are in short supply in the UK. Even those in unskilled work are probably not displacing many local workers: these jobs tend to pay at or near the minimum wage – if employers hire immigrants, whose English is sometimes patchy and who often move on quickly, it must be partly because the locals are unwilling to take these jobs.

First generation immigrants tend to live in the most economically dynamic parts of the UK. This is inevitable – immigrants are drawn to where the work and opportunities are. But these areas are also wealthy and dynamic because of their openness. Contrary to popular myth, the areas of greatest immigration are not the ones with the greatest hostility to migration. London, for example, is easily the most tolerant region of the UK. The areas where there is most hostility to immigrants tend to be those where there are fewest immigrants, or where cultural and religious differences are pronounced, as in some northern English towns.

Openness largely explains London’s long renaissance and emergence as the only world city in Europe. It is perhaps the UK’s most precious economic asset. Huge amounts of tax revenue are redistributed from London to the rest of the country. According to the Centre for Economics and Business Research, one in every five pounds earned in London goes to subsidise other regions of the UK. Without this redistribution (and a smaller but still very large one from the rest of south-east England), the bleak economic prospects of swaths of Britain would be even bleaker. Of course London should be supporting the rest of the UK; it is easily the wealthiest region of the country. But the British government needs to resist popular pressures for controls which would erode London’s ability to generate that wealth.

British politicians need to think about what policies are needed to help London and its environs exploit its unique position. First, they should reverse the cap on student visas. This ill-thought out step has already damaged British universities – one of the country’s most successful export-industries – by making it harder for people to study in the UK. The number of foreign students in Britain is a much envied source of soft power (many either stay or retain long-term links with the country) and export earnings. While other European countries urgently try and attract more foreign students, Britain fashions ways of deterring them.

Second, the government should lift or scrap the caps placed on non-EU skilled immigrants. Given the increasingly fierce global competition for such workers, it is self-defeating to limit the number allowed into the country.

Third, the government should stop stigmatising EU immigrants. There is no evidence of benefit tourism or health tourism. If anything, the reverse is the case; EU immigrants in the UK are on average much younger that UK ones living elsewhere in the EU, and more likely to be in work than the native population. If there is a country in the EU with legitimate cause to resent health tourism, it is Spain, which must cope with large numbers of elderly Britons.

Fourth, it needs to open the way for more construction. The crippling cost of property is now a serious threat to the prosperity of London and the south of England generally; unless action is taken firms will find it increasingly hard to entice people to work there. It will, in turn, be impossible to build these houses unless contractors can rely on imported labour. Britain has an acute shortage of skilled construction workers and there is little indication that the unemployed elsewhere in the country have any desire to do this kind of work in London. There is a reason why London’s building sites are full of Poles rather than Liverpudlians.

How should the government address the rising anti-immigrant feeling that threatens the UK’s economic vibrancy and even its membership of the EU? It can do little about ignorance, other than to stop legitimising it by playing up to it. Instead of scape-goating the migrants that Britain needs, the government should concentrate on addressing the underlying cause of the popular frustration: an acute shortage of affordable housing, even in many economically depressed parts of the country; a lack of vocational training for those that do not go to university, and over-burdened public services. If there is a shortage of primary school places in London, the answer is to build more primary schools. Most countries in Europe would do anything for this problem: with the populations ageing rapidly, European countries (including Britain) need all the young people they can get. If the NHS lacks capacity in London, expand that capacity. After all, immigrants pay tax. Indeed, the OECD calculates that in the UK they pay more into the pot than they take out.

Britons, especially those living outside London, will all be much the poorer if politicians fail to challenge the widespread belief that immigration is a burden rather than a boon.

Simon Tilford is deputy director of the Centre for European Reform.