We are now just over one year into an era of left-of-centre governments on both sides of the Channel; the first time for 50 years that experiments in socialism (if new Labour will forgive the word) have been conducted simultaneously in France and Britain.
Peter Mandelson, the minister without portfolio and the master-tactician of the Blair government, was at the National Assembly in Paris yesterday to mark the anniversary. He had been invited to debate with his French alter ego, Francois Hollande, general secretary of the Socialist Party, the similarities and differences between Blairism and Jospinism.
It was a fascinating debate, except that both men supported the same proposition: that the two governments are pursuing similar policies in two very different countries, which are perhaps not so different in the end. "Britain and France have much in common. Blair and Jospin have even more in common, perhaps more than people realise even now," Mr Mandelson said. "Both Blair and Jospin have succeeded in restoring confidence in politics and confidence in politicians," said Mr Hollande.
Not much scope for controversy there, then. What has become of the fraternal jealousies between the Labour Party and the Parti Socialiste? A few months ago some new Labour people were making snide remarks about the "old Labour" Jospinists with their 35-hour weeks; and some French Socialists (notably Martine Aubry, the employment minister) could not disguise their exasperation with the born-again evangelism of new Labour.
Since then, Tony Blair's triumphant domination of British politics has continued, with only a few dents and doubts; Lionel Jospin, against all expectations (in Britain at any rate) has become a quietly competent success. The French economy is humming (give or take a few strikes); unemployment is falling; Mr Jospin has higher poll ratings (just over 60 per cent) than any other French prime minister has ever recorded after a year in office.
The two governments, whether they admit it or not, remain rivals in an undeclared race to invent an intelligent, durable new formula for left- of-centre European politics in the next century. But they seem, increasingly, to be friendly rivals. The two parties have set up study groups on social exclusion and the future of the European Union.
Unlike the mutually uncomprehending British and French socialist politicians of recent history (witness the Mitterrand anecdote) the Blairists and Jospinists appear to be easy in each other's company. The great exceptions are the two finance ministers, Gordon Brown and Dominique Strauss-Kahn, who do not get on.
Mr Mandelson, talking briefly after yesterday's lecture, admitted that "things got off on the wrong foot" between the two governments last year; or at least in the media presentation of relations between the two. "That's why today's event was important," he said, unable to resist the temptation to "spin" a journalist, wherever he might find one.
But just how similar are Blairism and Jospinism? Messrs Mandelson and Hollande put up strong arguments for the family likenesses. Both governments are committed to educational reform as the strategic weapon of economic success in the next century; both have introduced programmes of youth job creation; Mr Blair plans a French-style minimum wage; Mr Jospin talks of encouraging economic dynamism while maintaining "social solidarity"; Mr Blair ditto, while talking of maintaining "a strong community".
Both men are trying to push through constitutional reforms which would modernise their countries' democratic systems. Both men have been lucky in strong economies and the hopeless state of their oppositions.
But there are equally telling differences. In a sense, there has been a bizarre reversal of the traditional British and French roles. It is Mr Jospin who is the true steady-as-we-go pragmatist; Mr Blair is the ideologue, fond of sweeping phrases.
Mr Blair inherited a booming economy, in which many of the blockages which still afflict France had been cleared away by the Thatcherist pain cure of the Eighties. He also came to power with a huge majority of one party. Mr Jospin inherits a French system which is permanently attempting reform and permanently fearful of reform. His majority is a coalition of socialists, of various independent persuasions, Communists and Greens.
Mr Blair has applied a grand design to a clean page; Mr Jospin has been forced to tinker, fudging here, taking a bold decision there. Given these differences, it is remarkable how many similarities have emerged between the programmes of the two governments. (The main differences remain over labour market policy, with Mr Jospin heavily committed to the interventionist, 35-hour week.)
If the Social Democrats come to power, as expected, in Germany in September, all of Western Europe's big three nations will have centre-left governments for the first time in EU history. In terms of dash, glamour and self-publicity, Blairism will be the model for the SPD's chancellor candidate, Gerhard Schroder. But he will inherit problems closer to those of France - a parliamentary coalition, a top-heavy state. He may end up governing more like a Jospin.