BORDER posts are going up all over the world, and we may not see them closed in our lifetimes. The pious hopes that the war against Covid-19 would unite the world are evaporating as countries lock out immigrants.

Donald Trump closed the US borders yesterday to all immigrants in a tweet that was widely criticised as “xenophobic and racist” – an attempt to cover his own incompetence. Yet caring, sharing Jacinda Ardern has done exactly the same in New Zealand. No foreigners have been permitted to enter since the Antipodean country the lockdown.

Nor is there any certainty that New Zealand’s borders are going to reopen any time soon. At the very least, future immigrants will have to put up with quarantine and long delays if they are allowed into the country at all. It’s a Brexiter’s wet dream.

In Scotland, the Government is under pressure to explain why, as The Herald reported recently, 8,000 people have been allowed to enter the country apparently with barely any health checks at all. This seems to be a UK policy. Border controls are not devolved, and the UK Government seems to want to keep airports open for business.

SNP MSPs and MPs are also talking about closing Scotland’s border. MP Joanna Cherry has demanded, at the very least, rigorous health checks and quarantine at airports. Commentators, like our own Neil Mackay, are calling on Nicola Sturgeon to detach Scotland from the failing Westminster Government and introduce a rigorous independent policy of test, track and trace following Germany’s lead.

You only need to look at what is happening in Singapore to understand why voters are concerned about the UK’s laissez-faire approach to border security. This scrupulously tidy city state had been the poster child for Covid management. Thanks to its experience of SARS a decade ago it was well prepared.

The lockdown was rapid and the country adopted mass testing and contact tracing from the start. By the beginning of April, Singapore seemed to be well on top of he disease. Then came the second wave.

On Monday, Singapore recorded more than 1,400 new cases of Covid 19, its highest ever. The country of five million people now leads south-east Asia in the virulence of this disease.

Epidemiologists warned governments from the start that lockdown can only be temporary and that Covid will get through eventually. And in Singapore it just has.

And who are they blaming? Well, the one million migrant workers, from countries like Bangladesh, who sweep the city streets and tend its butterfly gardens. The most virulent new outbreak is in their cramped dormitories.

The Singapore authorities have quarantined thousands of migrant workers into what are to all intents and purposes Covid concentration camps. Eye witnesses report squalid conditions, rats and poor food.

Now, New Zealand is one of the most liberal and open societies in the world. But it is going to allow migrants to enter the country freely any time soon? Is it going to allow the four million or so annual tourists? My daughter is one of them. She’s been in a Queenstown backpackers hostel under lockdown for the last month.

The ethnic dimension to Covid is going to be a huge issue in the near future. It’s already clear that BAME people are more prone to getting this disease. That may be genetic, or it may be to do with their social circumstances and over-crowding. But it means that, in authoritarian countries, they risk being singled out for epidemiological social cleansing.

Covid is changing the world in dramatic and disturbing ways. We are seeing a big increase in economic nationalism. The European Union has been riven with tension over Germany’s reluctance to share the Covid-related debts of Italy.

Global companies are suffering billions in losses from the disruption of international trade and are repatriating supply chains. This re-shoring, as it is known, had already been happening before Covid, as wages have risen in China, making manufacturing there less attractive.

Apple can’t market its new phones because of disruption to factories in China. It can’t rely on foreign sweatshop labour any more because the sweatshops are going to be transformed to combat the disease.

But the pandemic has added yet another dimension to it. There is huge uncertainty about when and if borders will relax. It is beginning to look as if we may have economic disruption until a vaccine is found, and even after that.

This is why Mr Trump’s much-criticised travel ban makes a great deal of sense from his nationalistic, America First, politics. The President’s Twitter rants seem arbitrary, contradictory, callous and unthinking. And they are. But they are also politically astute.

The Democrats have got themselves into a mess by attacking Mr Trump’s border closures. They accused him of racism when he banned flights from the European Union back in February. And again today. But his voters only see him following the example of other countries.

America is a vast country, with a diverse economy providing most of what it needs from corn to cars. It could effectively shut the world out. Indeed, the US is arguably much better placed to do that than New Zealand because it can do without many of the imports other more open countries depend on.

Here, SNP supporters argue that, since Scotland’s death rate is currently running at around half of England’s, Ms Sturgeon should be following Jacinda Ardern and locking the border. There is immense frustration that Nicola Sturgeon appears to be dictated to by the UK Government.

Health is devolved and the Scottish NHS could have pursued a different policy. However, as this column has repeatedly pointed out, the Scottish Government is following the same scientific advice as England. There is no evidence that Ms Sturgeon would have followed a different course had Scotland been independent.

But social media is echoing to demands to lock foreigners out of Scotland for safety’s sake. Ms Sturgeon is an internationalist and will never do that. But the resurgence of nationalism across the world is making borders ever more important to voters. Face up to it: the age of globalisation and free movement is over.

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