Will referendums be the undoing of the European Union?
And is the much-argued-over EU constitution doomed from the start by the requirement to have it ratified by every member state - in some cases by referendum?
These are the questions that seem to spring from any analysis of Sweden's vote last September on the single currency, and of earlier referendums in other countries - Ireland's on the Nice Treaty and Denmark's on the euro.
The votes are rarely, if ever, merely about the question on the ballot paper.
Experts interpreted the Swedish euro vote as a rebuff to the EU
Electorates tend to use them to express their views more generally on the EU and European integration.
When the Irish first voted on the Nice Treaty, billed as paving the way to the enlargement of the EU, the campaign concentrated on issues such as neutrality, defence and abortion.
The No vote reflected those distinct Irish concerns, certainly not a desire by the Irish to prevent new members joining the EU.
Denmark's campaign on the euro in 2000 was similarly dominated by fundamental questions about Danish sovereignty and the ceding of powers to "Brussels".
In Sweden too, voters in the street often did not even refer to the economy or the single currency when asked about their reasons for voting one way or the other.
Instead, they answered in terms of "we have to be together with Europe", or "we need to preserve our independence (or traditions or way of doing things)".
This helps to explain why there was a slight majority in favour of the euro in Stockholm, while rural areas generally voted overwhelmingly against.
On purely economic issues surrounding the currency, there was no reason why rural and urban Swedes should vote differently. Rather, the difference reflected the more open, cosmopolitan, "Europe-friendly" feelings of people in the capital city, compared to the more traditional values of the countryside, with its nostalgia for Sweden's "separate identity".
Almost all commentators on the Swedish rejection of the euro interpreted the vote as a rebuff to the EU, not just its currency.
Margot Wallstrom, Sweden's EU Commissioner, said the No campaign had built on Swedish euro-scepticism which had been there ever since the 1994 referendum on joining the Union.
Better "political leadership", she said, could have led to "better knowledge about the rest of Europe and to a better feeling for Europe".
Prime Minister Goran Persson said the vote revealed "profound scepticism towards the European project".
European Commission president Romano Prodi, repeating thoughts he had after the Irish No to Nice, remarked that the Swedish vote demonstrated the need to bring Europe closer to its citizens.
It is recognised, in other words, that EU referendums - on any subject - are used by voters to vent their feelings about Brussels.
This augurs badly for the new constitution. Not all states will put it to a referendum, but those that do will know that voters will take the chance not so much to approve the fine print of a complicated legal text, but simply to pass judgment on their membership of the EU.
Countries like Sweden and Denmark could easily throw the entire project out, especially as their highly active anti-euro movements will portray the constitution as a major step towards further integration and loss of sovereignty.
The defeat of a referendum on the constitution in the UK would not just affect Britain but the entire EU, leaving two years of painstaking work by Valery Giscard d'Estaing and his fellow constitution-drafters in pieces.