Cast your mind back, if you can, to the summer of 1983. François Mitterrand was President of France and the French Socialist Party led a government containing four Communist Party ministers. Times were good for the English tourist. One pound bought 12 francs. A good lunch in the Dordogne was yours for a snip.

Times were less bright for the French. The extensive nationalisation of French banking and industry combined with significant increases in public spending on pensions and other social benefits had produced a jump in inflation, an alarming balance of payments crisis and two devaluations in eight months. A third devaluation was soon to follow.

Haunted by the Left's unhappy experience of government in the 1930s, Mitterrand and his supporters had to decide what to do: plough on regardless of the consequences, leave the European Monetary System, and embrace protectionism; or call a halt to their reforms, reign back public expenditure, and adopt a policy of economic "rigour".

The dilemma they faced was a profound and enduring one. In the 1920s Léon Blum, France's first socialist premier, had drawn a distinction between the exercise and the conquest of power. While the first indicated a left-wing majority in parliament, it was the second that began the transition to socialism. In 1981 the provincial and bourgeois Mitterrand had been elected on a mandate to "break with capitalism" but now, after only two years in power, this seemed little more than a pipedream.

In the event, Mitterrand opted for "rigour", the Communists withdrew from government, and the construction of Europe replaced the building of a socialist society as the primary political objective. If Mitterrand survived, he did so only through the deployment of supreme Machiavellian skill and by reducing his colleagues to servile and self-interested courtiers.

What remained — and what arguably still remains for the French socialists — was a glaring contradiction between a radical rhetoric and social-democratic pragmatism, between the language of opposition and the practice of government.