The current deep antagonism between Russia and Britain disguises some important similarities between the two countries. Those parallels are likely to become more obvious after Brexit — in ways that should worry both the UK and the EU.

Britain and Russia are on the fringes of the European continent. Partly as a result, the two have traditionally had a dual identity — regarding themselves both as European and as something more. Nearly 80 per cent of Russia’s landmass is in Asia. The British empire was built outside Europe and the country still has strong cultural ties with the “Anglosphere” in North America, Australasia and south Asia.

So it is unsurprising that the UK and Russia are likely to end up as the two major European powers that stand outside the EU. However, both countries will continue to worry about the EU’s collective power. As nations on the periphery, they have traditionally feared the rise of a single power dominating the European landmass — which partly explains why they ended up as allies in the Napoleonic wars and the two world wars. Each country has built its modern identity around the memory of victory in 1945. And both are shaped by nostalgia for imperial power.

For Britain, the Russian parallel is not encouraging. It underlines the danger that Brexit could lead to a long-term souring in relations with continental Europe, and a politics of embittered nationalism in the UK.

For Brussels, the danger is that the EU will ultimately be faced with two angry and alienated neighbours, in Britain and Russia. Both are great powers in European terms, with considerable capacity to make mischief.

It is of course true that Britain has a liberal and democratic tradition that is absent in Russia. That aligns London’s political values much more closely with Paris and Berlin than Moscow. Those values make it much less likely that the British political class will allow the country to “go rogue” in the manner of Russia under Vladimir Putin.

But geopolitics is not driven by values alone. There are also emotions and strategic interests involved. And here the parallels between post-Soviet Russia and post-Brexit Britain are concerning.

The economic turmoil and strategic setbacks of the 1990s convinced many Russians that their country had been taken advantage of by the west. Russian anger focused on the US and on Nato expansion. But the Kremlin also came to see the EU as a threat — since, in Moscow’s eyes, it was expanding into Russia’s natural hinterland. The Kremlin’s decision to intervene militarily in Ukraine was triggered by the fact that the country was about to sign an association agreement with the EU.

If Brexit goes badly wrong, it could trigger events reminiscent of the collapse of the Soviet Union — the break-up of the country, accompanied by a profound economic shock. English nationalists would undoubtedly see the EU as complicit in such malign events: some critics already accuse Brussels of manufacturing artificial problems on the Irish border, unreasonably delaying a free-trade deal and encouraging Scottish independence.

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For the moment, British and EU officials are careful still to talk the language of friendship and future partnership. But, beneath the surface and off the record, antagonisms are stirring. One influential former EU official argued to me recently that because Brexit Britain would be a threat to the EU, it is in Europe’s interests to encourage Scottish independence and Irish unity. (Wine had been consumed — but in vino veritas.) When, with the Russian parallel in mind, I suggested that it would be a bad idea to humiliate the UK, I was told that Britain was responsible for its own humiliation; and besides, the UK had humiliated the EU by voting to leave. (“You said you are better than us.”)

Even on the record, you can hear hints of rivalry stirring. Angela Merkel, Germany’s chancellor, usually the voice of moderation, said recently that Britain will be a “competitor” to the EU after Brexit — bracketing it with China and the US.

If, as seems likely, the EU responds to that perceived competitive threat by refusing to move towards tariff-free trade with Britain, then antagonism between London and Brussels will grow. The Europeans will argue, with some justification, that Britain has brought its sorry fate upon itself — just like Russia. But winning the debate would not head off confrontation.

In an increasingly bad situation, the UK (or possibly just England) would play what few cards it has — cutting back on security and diplomatic co-operation with Europe, and working with forces that are hostile to the EU.

These threats are not taken very seriously in EU capitals at the moment because Britain is in such a mess. The same dismissive attitude was adopted towards the Russians in the 1990s. After all, their country had just fallen apart and their economy was in freefall. But, spurred on by a feeling of humiliation, Russia reasserted its power — in ways that the EU now finds alarming.

The lesson is that countries that have been major European powers for centuries are unlikely simply to drift into irrelevance. Their interests need to be accommodated. If that cannot be done, they will have to be confronted. Either way, a European construction that excludes Britain and Russia is unlikely to be either stable or secure.

gideon.rachman@ft.com

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