Over the years the piecemeal reform of the European Union has been accompanied by little discussion of what might be termed "the end of the road". Such talk, it was argued, might frighten the horses.
But enlargement has concentrated minds again on the issue, and in the spring two former heads of government opened a new debate. France's Mr Valery Giscard D'Estaing and Germany's Mr Helmut Schmidt, backed by the former Commission President, Mr Jacques Delors, suggested that to preserve Europe's dynamic an inner core group should integrate themselves further, creating a treaty within a treaty and new institutions.
In May, Germany's Foreign Minister, Mr Joschka Fischer, entered the fray and governments sat up and noticed.
"Quo vadis Europa?" he asked. How could a Europe of 30 states, as presently structured, function in a way that was understood by its people?
He saw the solution in "the transition from a union of states to full parliamentarisation as a European federation". An EU government would be elected by MEPs.
But Fischer's federation was a new form of creature. "Only if European integration takes the nation states along with it into such a federation . . . will such a project be workable."
To that end he argued for a bicameral Parliament, one chamber with national parliamentarians, the other, directly elected. And to provide the dynamic to get us there he too suggested that a few states, perhaps the euro-group, create an avant-garde for the integration process.
France's President Chirac welcomed the initiative and urged a debate after the IGC on the EU's constitutionalisation, the reorganisation of the treaties, and a definition of competences.
The Prime Ministers of Belgium and Britain have now joined in, both echoing calls for a second chamber involving national parliamentarians. But while Mr Guy Verhofstadt argued for the direct election of the Commission President, Mr Blair made clear he did not want any further federalising.
He called for an expanded role for summits to define the European agenda annually, and urged the drafting of a political declaration setting out "the principles according to which we should decide what is best done at European level and what should be done at national level, a kind of charter of competences".
The role of the new second chamber would be entirely to police such a "charter" to guarantee the prerogatives of national parliaments.