Western liberalism was built on the principle of marrying out. Our beliefs about the freedom of the individual ultimately stem from the Catholic Church’s ban on cousin marriage, which helped create a worldview that was open, trusting and opposed to both clannishness and xenophobia.

The medieval Church’s insistence that marriage be consensual was revolutionary and strange; back in the 13th century a romantic poem, The History of William Marshal, has the protagonist coming across an eloping couple who have defied their parents to seek true love. Our hero then robs them, and since the story was commissioned by Marshal’s sons to glorify him, we can assume that public opinion might have thought this the right thing to do.

Yet three centuries later a popular playwright was able to write a story in which the audience sympathises with star-crossed lovers defying their parents’ wishes. Czech social scientist Karl Deutsch called this change of attitude ‘the Romeo and Juliet revolution’, and romantic freedom was intimately tied up with individualism – the idea that a person must be free to make their own life choices, rather than doing what is best for their clan.

Because the right to marry for love is central to our idea of individual liberty and personal happiness, many people strongly object to anyone who might stand in the way, whether it’s the Montague and Capulet patriarchs or the Conservative party.

So the government’s new marriage restrictions for foreign spouses have been harshly criticised, with many couples now denied a chance of happiness. The reason for this change of policy is that the Tories are at disastrous polling levels, almost bad enough to send them into Canadian-style extinction at the next election. They are even losing votes to the tiny protest party Reform – and were Nigel Farage to return from the jungle to lead that movement, the Conservatives might well come third.

The biggest headache is the huge rise in immigration post-Brexit, carried out both for economic and ideological reasons, but extremely unwise politically. After 2016 Tory and Labour voters realigned considerably on the issue of immigration and multiculturalism, and yet despite this the governing party ramped it up.

Immigration salience tends to rise and fall with immigration numbers, and while Brexit briefly took the wind out of the issue, public concern has once again followed the underlying figure.

It is not just that the numbers are large, but unselective. In the Telegraph, Sam Ashworth-Hayes writes that:

Just 335,000 of those coming in the year to September arrived on work visas. The numbers were made up by their 250,000 dependants, some 486,000 students, 153,000 dependants of students, and a surge in humanitarian and family visas (a little under 200,000)

This is not immigration as economic rocket fuel, but as a short-term patch. The dependants of people brought in to avoid paying British care-home workers more are unlikely to add significant economic value, and we can see this in the data; only 25 per cent or so are in work.

People arriving on social care visas are exempt from paying the NHS surcharge, and tend to work in low-paid roles. There is a good chance that they are a net fiscal drain even though they cannot claim benefits; the rest of the country pays for the schools their children attend and their healthcare, too. Other indicators bear this pessimistic perspective out. Despite many theoretically being selected for their ability to work, foreign-born residents are more likely to live in social housing than those born in the UK. In a country with a chronic housing shortage worsened by immigration, this is adding insult to injury.

So like panicking pilots heading towards the ground, the Tories are desperately pushing at any button, hoping one will magically save them from oblivion, and have hit on marriage. Yet while this new rule would have prevented low tens of thousands out of last year’s 1,180,000 migrants from arriving, at the same time potential migrants can still apply for a skilled worker visa if their salary is less than £26,000 but their job is in a ‘shortage occupation’ – and also bring dependents. (Although the government has also outlined plans to restrict other routes, which one must treat with a certain scepticism.)

This means that, perversely, the new rules may give foreigners more rights than British citizens in bringing a partner. According to the Migration Observatory at Oxford University, ‘in some circumstances, British workers would face more restrictive rules on family than migrant workers in the same job’ and ‘health professionals in the NHS who come to the UK on skilled work visas would be able to bring their non-UK citizen partners with them.’ So foreign nurses can bring over a spouse but British nurses can’t.

The new rules also mean that British professionals working in places like Singapore, Australia or the US are going to find it very difficult to move back with foreign-born husbands or wives, and these are just the people we want to return. The cost of compliance is already quite a burden, with various fees involved in trying to win over the Home Office.

The rule is particularly onerous becauseit only measures UK earnings. If you have a job in the US and marry an American, for example, you can’t get a British visa for them based on your American salary, but first have to move home, get a job, pass the earnings threshold and then apply for them to join you.

This seems both personally cruel, and unhelpful for the British state – so why has the government pushed this particular button? Firstly, when it comes to immigration, numbers attract headlines, and the numbers are astonishingly high. Yet while crude measurements are better than none, numbers are not the only problem – it’s just easier for the government to reduce this particular inflow, even if it means punishing high-productivity white-collar professionals based abroad.

On top of this, it’s also a good example of immigration concern being driven by taboo, and an unwillingness to say who we don’t want arriving. Instead the system tries to be ‘fair’.

British citizens marrying foreigners is not a problem, sham marriages within particular communities are. It is chain migration, through family reunion, which has the most negative social and economic effects.

When Labour came to power in 1997 one of the biggest mistakes they made was to abolish the ‘primary purpose’ rule, which required that newlyweds show that immigration was not the primary purpose of their marriage. This, activists complained, was racist. Indeed, it was designed to specifically stop members of minority groups using marriage to obtain British citizenship. And it was a good policy.

Abolishing the primary purpose rule led to a situation where, according to Christopher Caldwell, ‘Fully 60 per cent of Pakistani and Bangladeshi marriages [were] to spouses born abroad, a major factor in the roughly 50 per cent growth of the Pakistani population of Manchester, Birmingham, and Bradford over the 1990s.’ This not only sharply increased the size of these communities but also reinforced the culture of the old country and reversed integration. Often not only were spouses from the same ethnic group, they were from the same family, with UK citizens married off to cousins from the old country.

The most segregated Pakistani and Bangladeshi communities in Britain have not fully undergone the Romeo and Juliet Revolution, coming from cultures which are still clannish, making integration very difficult. Marriages were often forced, and resulted in a number of honour killings, which were annually in double figures by the time Labour left power.

This form of chain migration is extremely damaging to social cohesion, and becomes harder to control once a minority population becomes large enough. The only way you stop it is by clamping down on marriages. But because of taboos about openly saying who we wish to let in, we instead employ very crude measurements, and apply these rules far more widely.

Immigration taboos also lead to proxy arguments, the classic example being the EU and Brexit. The rising salience of immigration in Britain, and the rise of anti-immigration parties, first the BNP and then Ukip, came about with the rapid growth of segregated, largely south Asian communities from 1999 – before EU immigration ramped up in 2004. Indeed, both Leave and Remain voters preferred EU to non-EU migration, but because of taboos about discussing the issue, the EU became a proxy for immigration concerns. Immigration drove the Brexit vote, but even the argument about ‘control’ enabled senior Tories to convince themselves that it was wise to increase global migration afterwards.

Avoiding the real issue results in bad policy decisions, and the marriage rule is another example. It is in part designed to stop sham marriages and chain migration – unions that increase the separation of a minority group – but because it is so crudely applied the net drags in people who wouldn’t be a problem, and ends up needlessly making our lives worse.

Immigration policy should be directed towards serving the interests of British citizens and making their lives as convenient and happy as possible. Any restrictions will lead to hard cases having their hearts broken, but more selective rules can still minimise this human cost.

It should be a formality to bring in a spouse from another rich country, while having rules to make it difficult to do so from states which enable chain migration. A British professional overseas who wants to return with a Singaporean, Italian or Canadian spouse shouldn’t have to jump through hoops or spend a fortune in legal fees – they’re paying a high premium on an insurance policy which doesn’t usefully discriminate.

Numbers matter, but they are not the only story. The most beneficial sort of immigration comes from countries of relatively equal wealth, and the social cost of free movement between rich countries is minimal.

But because immigration concerns are so wrapped in taboo, the authorities are only able to use extremely crude and arbitrary rules. And so Romeo and Juliet must live apart.