As Francois Hollande saw rising unemployment and taxes drive down his opinion poll ratings, the last thing he needed was for his education minister to produce his own banana skin and tread on it.
For Vincent Peillon, who had enough on his plate as France's new socialist government planned radical changes in education, it should have been a routine appearance on a Sunday night political radio programme. But he caused his president acute embarrassment by calling for debate on the decriminalisation of cannabis. By the time he had been hauled over the coals by Mr Hollande's prime minister, Jean-Marc Ayrault, the damage had been done.
It was not lost on the education minister's critics that this is an issue that goes straight into the classroom. One campaign group, Test Cannabis, estimates that the average age at which pupils discover the drug is 15. Among 13 to 19-year-olds, half have tried it at least once by the age of 17, one in five smokes it 10 times a year or more and one in 10 several times weekly.
Gleeful political opponents seized on Mr Peillon's comments as a classic gaffe, adapting the common taunt "gauche caviar", which English speakers would translate as "champagne socialism", to "gauche petard", branding him a "firecracker" or loose cannon of the Left.
The essential argument advanced by Mr Peillon is familiar enough: remove the criminality of smoking a joint and you eliminate the dealer (provided, of course, that the dealer sells only cannabis).
Rebuking French reluctance to deal as openly as some European countries with the problem, he said on the France Inter radio station: "This is a major issue. Almost every night on television I see reports on illicit trafficking in our suburbs and the dangers in which our people - schoolchildren included - live. As minister of education, I see it as an issue directly affecting our youth. There is a parallel economy in this country, that of the drug economy."
This sparked an almost immediate defensive reaction from socialist leaders, and the Right made the most of it. Jean-Francois Cope, a candidate for the opposition UMP leadership, said that far from liberalising the law on cannabis, schools should introduce screening to detect users.
Mr Ayrault gave Mr Peillon, who was reportedly ready to resign, a stern dressing down, warning that any further deviation from the party line would lead to dismissal.
Other reactions have been more surprising. Two unions representing secondary education teachers, and another concerned with children's health, strongly defended Mr Peillon's right to raise the issue and said that they, too, favoured debate.
Emmanuel Protin of SNALC, the second-largest union for teachers of children aged 10 and above, agreed on the need for more open discussion, but made it clear his union was not taking a pro-decriminalisation line.
"Our concerns are much more with the issues facing the teachers we represent," he said.
"It is important not to confuse what happens inside the school and what happens outside."