In Brussels and across Europe there has been a surge of interest in the British general election campaign. People had more or less accepted that David Cameron would form a Conservative government, probably with a large majority, but now the outcome looks far from certain.
Mr Cameron's insistence on removing his MEPs from the mainstream centre-right European People's party into the arms of a small right-wing faction was greeted with incredulity in Brussels. His speech last November in which he set out his stall of anti-European Union policies caused deep alarm. The publication of the Tory election manifesto earlier this month confirmed Brussels' worst fears.
The Conservatives pledge to amend the Lisbon treaty to return EU powers to the UK in respect of the Charter of Fundamental Rights, criminal justice and social and employment law. Maintaining the party's hostility to Lisbon, the manifesto proffers a "UK Sovereignty Bill" which would overturn the primacy of EU law and undermine the authority of the European Court of Justice.
Mr Cameron's pledges amount to nothing less than an attempt to revise the terms of British membership of the EU. That such a renegotiation would prove to be futile (because none of the other states, to say nothing of the European parliament, could ever agree to it) is neither here nor there. The very attempt to destabilise the EU by unhitching Britain would be hugely disrupting, especially at this time of economic and financial peril.
Labour's record on Europe since 1997 has disappointed even fellow socialists. Early promise was dispelled by a fairly grisly record. Britain's refusal to join the euro when it could and should have done is resented. Its reactionary attitude to the constitutional development of the EU - especially its hostility to the European parliament - has caused endless frustration.
The UK's multiple opt-outs from integrated policies in the field of fundamental rights, justice policy and home affairs are rather scary. Over-zealous protection of the narrow interests of the City of London is deemed to have contributed to the financial crash. The invasion of Iraq and obsequiousness to the US set back efforts to build a European common foreign and security policy. Despite much rhetoric, the UK has not followed through Tony Blair's original St Malo agreement with French President Jacques Chirac to reinforce military collaboration between their two countries. And since Mr Blair left office in 2007, even the rhetoric has declined.
So the Liberal Democrats' successful campaign has gone down well in EU capitals. Nick Clegg is something of a known quantity in Brussels, having been a student at the College of Europe in Bruges, a Commission fonctionnaire, and then, from 1999-2004, an active MEP.
Speculation on the result of this suddenly fascinating UK election is rife. The French newspaper Le Monde surely spoke for Europe in pitching for a British coalition government between Gordon Brown's "eurorealism" and Nick Clegg's "euroenthusiasm".
Yet the thing that has galvanised continental political interest is the exposure of the iniquity of British electoral procedure. That Mr Brown could come third in terms of the popular vote yet still retain the largest number of seats in the Commons, and return as prime minister, is thought to be scandalous. Indeed, if such a result were to be declared in any benighted east European country, MEPs would pass cross resolutions about corruption and the abuse of fundamental rights.
Whatever comes out in the wash after May 6, a change to a system of proportional representation in Britain, where seats won at Westminster broadly match votes cast in the country, is a precondition for the rehabilitation of Britain's reputation as a democracy.
Electoral reform is also the necessary precondition for the achievement of a bipartisan European policy. Sterling will never join the euro as long as one British party (or another) threatens to overturn the move. There will not be a more measured tone to the European debate in Britain until a cross-party consensus can adopt a pragmatic attitude towards the EU's federal goals. Britain's interdependence with its EU partners is self-evident to anybody who bothers to look. Its national political parties can no longer claim, at least with credibility, that they can solve the country's problems on their own.
The normalisation of Britain's relations with the EU would enhance British influence in the current debate about how and when to complete the single market, especially in the field of financial services. The UK could really take a lead in building the security dimension of the EU, both internal and external. Its relatively high standards in agriculture, education and R&D could shape the formation of future EU policy. A Britain with a positively pro-European government could call the bluff of the French and Germans in the critical negotiations soon to start on the reform of the EU budget. Britain's traditional liberal instincts in international trade and overseas development policy would help the EU become the global actor it yearns to be. Enhanced British influence in Brussels would help and not hinder President Obama in transatlantic relations.
All this and much more besides will depend on whether there can be a more settled view at Westminster about Britain's EU membership. Such stabilisation will flow from electoral reform, as well as from a change of practice and attitude towards dealing with EU affairs in the House of Commons.
Britain's general election comes 60 years after the Schuman Declaration launched the idea of the integration of the Franco-German coal and steel industries. On that foundation was the modern European Union built - "the first concrete foundation of a European federation indispensable to the preservation of peace", as Jean Monnet wrote. Sixty years is long time for the UK to watch and wait on the sidelines. This week's election result may, just, be the time that Britain steps forward with confidence as a modern European country.
Follow the party's activity on...