I originally wrote this opinion piece for the Danish newspaper Jyllands Posten, which they translated into Danish (you can read the Danish version here.)

‘More EU? No Thanks!’ shout the posters at me as I walk along the street. As a Briton, I’m quite used to this kind of anti-EU rhetoric. But this isn’t London – it’s Copenhagen.

While the battle over Thursday’s referendum intensifies, few outside Denmark will have any idea it’s even happening. After all, does anyone really care if Danes opt in or stay out of the EU’s Justice and Home Affairs rules? Even a large proportion of Danes themselves seem unsure what the referendum is really about, with around a quarter yet to decide whether they’ll vote yes or no.

But there’s one European country that should be watching this with interest and that’s the United Kingdom. Within the next two years, the UK will hold its own referendum. This won’t simply be about European policing or legal matters. The question British citizens will be asked could affect the whole stability of the European Union; do voters want to remain a part of the EU or do they want to leave altogether? No wonder Prime Minister, David Cameron, is keen to prove he’s doing all he can to secure a better deal for the UK. But, as Danish Statsminister, Lars Løkke Rasmussen is discovering, it isn’t easy.

Yes and No posters

Back in 2013, the government at Westminster opted out of 130 EU criminal justice and law enforcement policies. It was an attempt by Mr Cameron to repatriate powers back from Brussels in order to appease the Eurosceptic wing of his own Conservative party and the UK Independence Party. But after 18 months of fractious argument, ministers finally secured parliamentary approval to opt back into 35 measures. These were considered essential for national security and included the controversial European Arrest Warrant.

That decision has been used by Mr Rasmussen as good reason why Denmark should follow a similar path. Opt in to the Justice and Home Affairs rules, including Europol, and Danes will have more control over policing and the country’s safety, he says. With terrorism on the rise, that has to be in the nation’s best interests, claims the ‘Yes’ campaign.

The Danish People’s Party (DF) NO campaign

But just like his British counterpart, Mr Rasmussen is facing a tough time from Eurosceptics. Dansk Folkeparti (DF) is doing a pretty good job at turning the whole debate into one about sovereignty and national identity. Vote ‘yes’ in this referendum, claims DF, and you will be opening the door to European asylum and immigration policies next. Rasmussen may have ruled this out, but given the current refugee crisis, DF is successfully using this argument as a weapon of fear. And anyway, the party claims, whatever the other side argues, of course we can stick with the current parallel agreements so there’s no need for ‘more EU’.

No-one, though, can forget that Denmark has voted ‘Nej’ before – in the referendum on joining the euro. Eurosceptics across the continent will be delighted if voters in this small nation do so again, none more so than those in the UK. They may be very different votes, but if the Danes can do it twice, what’s to stop the Brits from doing it just once? So we watch, and wait.