Boris Johnson makes me hopping mad. A couple of weeks ago, as you certainly know unless you’ve been hiding in a cave somewhere, he announced that he favoured a British exit from the European Union. Now, his reasons for this – his various cunning little schemes, his double-bluffing, his jostling for Conservative leadership – I don’t want to get into, or we’d be here all day. The point is: the current Mayor of London came out in favour of Brexit, with still a couple of months’ active mayor-time left to serve. And so did the Conservative candidate to potentially succeed him, Zac Goldsmith. That, to me, is pretty shocking, and allow me to tell you why.

After the 1993 Maastricht Treaty permitted free movement of labour within the EU (one of the “four economic freedoms”), lots of people started moving around. People from various countries moved to various other countries to live, work, study, start businesses, and so on. That was the idea. Naturally, a lot of them ended up in Britain, and naturally a lot of those people ended up in London. Over the next 23 years – that’s twenty-three years, almost two and a half decades – this movement continued all over the EU. Businesses thrived. Cultures were exchanged. Families were created. The cultures of the various European countries were not diluted and weakened into one boring, monotonous mass, as was feared by some. Quite the opposite: local cultures were respected, and largely strengthened. Like any group of societies, it hasn’t been without its problems, but generally the fusion of cultures has created a more colourful, cosmopolitan collection of places, and few cities have benefitted from this process as much as London.

So, Boris Johnson comes along in 2008 and finds himself mayor of a city of eight million people, of which, recent estimates suggest, 600,000 are EU nationals. These particular individuals have chosen not to seek British Citizenship, partly because it’s a lengthy, arduous process which costs close to £1500 (yes, even if you’re married to a British citizen), but mainly because not doing so was the whole point of the free movement of labour, which has been in place for the aforementioned 23 years. Now the EU Referendum looms, and nowhere (and I’d be delighted if someone could correct me on this) – but nowhere have I read or heard anyone, in any political capacity, stating what they expect to happen to these 600,000 people – let alone those in the rest of Britain – if we Brexit. I’m going to list a few possibilities, and I would suggest that the reader refrains from immediately scoffing, “oh, I’m sure that won’t happen” – because, again, I have no reason to believe anyone has the faintest idea.

1. They could be given a period of time in which to gather their things and return to their country of origin.
2. They could be asked to apply for Indefinite Leave To Remain and/or a work permit.
3. Possibility 2 could either fail, or take an inordinately long time (we can reasonably assume HM Revenue & Customs will be rather busy in the event of a Brexit vote), and therefore these people could be in line for Possibility 1.
4. Some arbitrary “long-term resident” rule could be invented, stating that people already living and working here prior to, say, 2010, could be automatically given Indefinite Leave To Remain and/or a work permit.
5. Everyone already living and working here at the time of a Brexit vote, or at the actual point of us Brexitting, could be welcomed to stay.
6. Free movement of labour from the EU could simply be permitted to continue; but given that this is one of the major bees in Brexit supporters’ bonnets, that seems unlikely.

One of the big problems is: Britain currently has little idea how warmly and/or cooperatively it will be treated by the remaining EU nations if we leave the EU. It’s conceivable, for example, that Britons will have to apply for visas to travel to the EU. I said conceivable. In his book The In/Out Question, Reuters journalist Hugo Dixon advises that “the best guess is that tit-for-tat would prevail… if we started requiring Romanians and Bulgarians to get visas before visiting the UK, the EU would probably respond by requiring us to get visas if we wanted to visit anywhere in the EU.” You may think this is highly unlikely, and maybe it is, but let me remind you: no one knows.

The inevitable result of all this “not-knowing” would be, in the event of a Brexit vote, an atmosphere of acute uncertainty. Individuals and families across the country will have long-term plans – houses, jobs, schools – put into disarray (just as British nationals living and working in other EU countries will also). EU nationals with careers in the UK may find their employers hesitant to promote them. New job applications may be tough, as perspective employers have doubts about the applicants’ long-term prospects. In short, it will bugger a lot of things up. Not sure about this? Show me something that suggests the contrary. Show me one high-profile Brexit supporter who has been able to say, as the expression goes, “this is what OUT looks like.” They… don’t… have… a… clue.

Now we return to London. Boris Johnson, the mayor of the city, is effectively saying he doesn’t give a hoot that some 600,000 of his residents would be plunged into turmoil. Zac Goldsmith is applying for the job of Mayor of London, while simultaneously backing a move that will deeply unsettle almost ten percent of the city’s population. Neither of these men has mentioned this. Both are instead concentrating on figures and economics, the former uttering jingoistic tripe about how marvellously strong and rich Britain can be on its own, the latter peddling quotes like “We [London] dominate in financial services, tech, media, culture and much more besides”. Does Goldsmith really have any idea what knock-on effect leaving the EU will have on this so-called “domination”? Finally, there’s the psychological question. How do you think the EU citizens living here personally feel, knowing that the mayor of their city essentially couldn’t give a damn about them? “Oh, come on,” you might think, “backing Brexit doesn’t mean he doesn’t give a damn about them.” Well, show me Johnson’s or Goldsmith’s long-term plan for these vital residents of our city. Show me the picture of a post-Brexit London either of these men have in mind. Because I don’t think either of those things exist.

The EU Referendum is not some random, figure-counting question where a decision is made by comparing numbers on a screen. It’s not even an important but largely political question, such as an in/out NATO referendum might be. The EU Referendum is about people. Without those 600,000 EU nationals, London would be an infinitely poorer place, in ways too numerous to mention, and if you think this is wrong, I would respectfully suggest that – very simply – you haven’t given it anywhere near enough thought.

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