Springtime for Europe. Magnolia buds jut from the bough, and the Netherlands is gripped by Euro-referendum fever. Or, if 'fever' is too strong, the vibe in Amsterdam's smokeasies is at least lightly tousled. For we're talking not of the UK's in/out poll on 23 June, but the one that really matters, here on 6 April, on ratifying the EU’s Association Agreement with Ukraine.

Everyone knows it’s a poll not just on the agreement but on the state of the European project. Mark Rutte, the Dutch premier, insists it’s only about commerce. That'll be news to Kiev. Ukraine’s president, Petro Poroshenko, desperate to join the EU, has hailed the treaty as facilitating accession: between 2003 and 2007, other Eastern European countries signed similar pacts before joining. With the treaty, as Poroshenko said last year, ‘Ukraine will be entitled to the status of candidate for accession.’ Rutte's claim is debatable, to say the least. The agreement’s commercial benefits to the EU are slight, given the size of Ukraine’s economy: one of the Netherlands’ twelve provinces, North Holland, has a bigger GDP than Ukraine. In a pre-referendum soaping foray to the Netherlands last November, though, Poroshenko agreed with Rutte – if not with himself – that it's all about trade: ‘For us, it's not about EU membership.’

Trade is never just trade. Poroshenko’s predecessor, Viktor Yanukovich, was turfed out after abandoning negotiations over the Association Agreement. Behind the deal lurk fear and loathing of Russia. Thanks to Putin, the Donbass war rumbles on; Crime’s annexation has sharpened Ukraine’s vulnerability. Last month’s conviction in Donetsk of a Ukrainian pilot on bogus murder charges hasn't helped. The Kremlin harbours misgivings about having another forward base for Nato’s nukes at its door. On his Netherlands trip, Poroshenko used the MH17 disaster to leverage Dutch opinion; he was feted by Rutte, the European Commission vice president, Frans Timmermans, and the king. But that probably won't be enough to swing the vote.

The plebiscite is being held because of popular demand. Under the Netherlands' new Advisory Referendum Act, polls on primary legislation can be triggered by 300,000 requests. A coalition against the EU-Ukraine Association Agreement, GeenPeil ('no poll'), managed to amass 428,000 requests, so the anti-treaty lobby is over the first hurdle. For a valid result, 30 per cent of eligible voters have to turn out, and a majority has to reject the treaty; opinion polls suggest that voters oppose it by more than 60 to 40. So would that zap ratification? No. The poll is 'advisory' only. The political elite, including Rutte, favours ratifying; against it is an infrared/ultraviolet coalition of the Socialist Party, Geert Wilders's PVV and the Party for the Animals. Rutte hasn't pledged to respect a 'No' vote. Meanwhile, Burgercomité EU, part of the coalition behind the poll, admitted on Friday that it 'couldn't care less about Ukraine' and that the exercise is a stalking-horse for 'Nexit'.

Another exercise in demockery beckons. The EU has form on this. When national referendums were held on ratifying the 2004 European Constitutional Treaty, Jean-Claude Juncker, now the Commission president, confirmed it was heads-we-win, tails-you-lose. ‘If it’s a Yes, we will say “on we go,” and if it's a No, we will say, “we continue.”’ When French and Dutch voters decisively rejected the treaty, Juncker was as good as his word. The Commission dissolved the people and elected another: itself. It reintroduced the rejected treaty provisions in the 2007 Lisbon Treaty, and governments ratified without referendum, except in Ireland (whose voters, having got it wrong first time, ratified in the resit). Not one to leave hyperbole at home when EU power’s at stake, Juncker warned in a recent interview with NRC Handelsblad that a 'No' from the Dutch to the Association Agreement with Ukraine would trigger a 'continental crisis'.

Empires like to expand under a unifying rubric: the EU is an empire in the Roman, Carolingian and Napoleonic tradition. Like the EU, those earlier exercises in integration were spurred in part by 'idealism'. Empires always think they benefit the natives, conferring such blessings as civilisation, prosperity, civic status. Natives' failure to value these blessings only confirms their backwardness. It makes a difference that cohesion isn't wrought by force of arms, but even then, policy often continues war by other means: the soft ordnance of trade sanctions against Russia, or the democracy-bypass conditions imposed on Greece over debt restructuring.

No doubt the EU won't take a Dutch 'No' for an answer. If they fail to get with the programme, decisions must be made behind the scenes, as with the EU's hush-hush negotiations over TTIP. Juncker again: ‘I am for secret, dark debates.’

Read more in the London Review of Books

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Tony Wood on the situation in Ukraine · 5 June 2014