"I don't mean a socialist revolution," adds Mr Krarup, a law professor at the University of Copenhagen and former firebrand of the Danish left. "No, I mean some kind of democratic revolution. The fact is that we Danes have been betrayed. We have said `No'. Yet the politicians are back again asking us to say yes. And still they don't tell us what their European Union is for."
Mr Krarup, who is also a member of the European Parliament - and a stalwart of the same anti-European party in Strasbourg as Sir James Goldsmith - is about to launch his revolution in court. He is to represent 12 Danes, including a trades unionist and a musician, who are challenging Denmark's constitutional right to give up sovereign powers to the EU. The case is adding to the ferment over Denmark's EU membership, which is once again dominating the country's political agenda.
Almost five years ago Denmark stunned the rest of Europe by saying "no" to the Maastricht treaty in a referendum which produced a vote of 50.7 per cent against. Only after Danish leaders had returned to the EU negotiating table, and won four "opt outs", did the population switch their vote, grudgingly, to a "yes". The Danes won opt-outs from monetary union, immigration and justice policy, European citizenship rules and defence co-operation.
Now, the country is heading for another bout of soul-searching. A new EU treaty, giving away more national sovereignty, is due to be signed in Amsterdam in June. Denmark must hold another referendum before ratification.
If Danes vote "no" again, the future of the union could be thrown into disarray. By failing to ratify, Denmark would prevent implementation of the new treaty across Europe, thereby blocking further integration and stalling the process of enlargement.
The social democrat-led coalition government is largely in favour of tying Denmark closer to the union. "We will certainly take a beating if we stay out of the single currency," says Niels Helveg Petersen, the pro- European Foreign Minister.
But after the shock of Maastricht, which demonstrated the danger of ignoring public opinion, the government appears reluctant to take a lead in the debate. All the polls show Danes are as sceptical today as they ever were. They, like the British, fear loss of sovereignty. But the Danes believe Britain distrusts Europe because it knows it cannot exercise its super-power ambitions in such a consensual forum.
Denmark, by contrast, takes a pride in the fact that it has no such vaulting ambitions. Rather, small and righteous Denmark fears it might be trampled on by bigger states.
Unlike in Britain, Danes fear that EU social standards will be weaker - not tougher - than standards in Denmark, where gay priests can marry (though not yet in a church) and where the state health system refunds the cost of a holiday, should a Dane fall ill abroad.
The Danish government is in a quandary about how to explain what Europe is "for". Uffe Elleman Jensen, the former foreign minister, ousted after the 1992 "no" vote, still talks of the need to promote the EU as a means to block German hegemony and maintain European peace. "We are still threatened by imbalances of power," he warns.
But many Danes see such arguments as dated. The government intends to use a different line to promote a "yes" vote in Amsterdam by explaining that the EU is "for" enlargement to the east, hoping this will give the project moral underpinning. But enlargement means little to most Danes, except the risk of more immigration.
There are signs that more liberal opinion formers in Denmark may be shifting towards EU support. Young moderates say it used to be the "decent" thing to be against but now it is "decent" to be pro. The far-right are hijacking the anti European agenda, producing a backlash.
Big business is strongly behind European Monetary Union. There is still, however, widespread evidence that ordinary people are deeply sceptical. Ask a taxi driver or a waiter whether they are against the union, and the chances are they will reply: "Yeh, sure" - as if to say: "It's obvious, isn't it?"
Tomorrow: The Danes and immigration