If Gordon Brown wanted an illustration of the cost of changing your mind in politics, he might ask Nicolas Sarkozy. It has been a bad week for the French President, but one that may do worse damage to his mission for reform than to his already battered popularity.

His main affliction this week has been the poisonous subject of the 35-hour week, created ten years ago by Lionel Jospin’s left-wing Government. On Monday Patrick Devedjian, head of the Union for a Popular Movement, France’s governing party, said that the law should be killed off. But Sarkozy slapped him down that evening. This is a mess, for Sarkozy and his centre-right project of shaking up France’s working practices. Nationwide transport strikes, to protest against his plans to make everyone work 41 years for a state pension, up from 40, do not help. Nor did last week’s teachers’ strikes, in protest against job cuts. Unless he wins some of these changes, the promises on which he was elected are in shreds. But at least with the strikes, he hasn’t lost the battle yet. On the 35-hour week, he has lost any claim to coherence, never mind the hope of success.

Jospin believed that cutting the working week from 39 hours to 35 hours, with no loss of pay, would shrink unemployment. It didn’t, broadly, although its precise effects are disputed. France has struggled to bring unemployment below 10 per cent; although the level came down to 8.4 per cent in 2007, the lowest level since 1983, a new way of stating official figures played a part. Companies say the rule is uncompetitive, but it has been popular in the public sector. In 2005 the National Assembly, dominated by the centre-right, voted to relax the rule for private companies, allowing more overtime, although it remained the standard in the public sector. One government after another has tinkered with overtime but not tried to get rid of the law itself.

So it was startling when, in Sarkozy’s campaign before last year’s election, he called the rule a “disaster” and vowed to scrap it. In January, he said that 2008 would be the year that the 35-hour week would die. But the next day, after a storm of rage from unions and the opposition, he backed down.

And there he stays, in a swamp of indecision, well back from the front line of change. It is a dreadful retreat for someone whose only clear mission was change. But how much damage it will do to his already punctured popularity is unclear (his approval rating is now at a record low for a president one year into his term). Polls show mixed feelings nationally about keeping the 35-hour week, and the same for support for the strikes.

Those mixed feelings are his problem. Many people want change, but not at their own expense. The French are not alone in this. It was always a moot question whether the constituency for change was as great as Sarkozy’s election suggested, or whether the people who voted for him would recoil from his actions as those came close to home.

But vacillation will make him look weak, without making him popular; the polls drive home the point that there is no popular course. So he might as well stick to his guns, and let his presidency be what it always was: a test of the national appetite for change.

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