IT WAS a double blow for France’s Socialist president, François Hollande. On October 13th, Marine Le Pen’s far-right National Front (FN) bagged a symbolic local by-election victory in southern France, having eliminated the left in the first round. The same day, the only Socialist minister running in a party primary for next year’s mayoral race in Marseille was evicted from the second-round run-off. Such results may be small and local. But they reflect a bigger credibility problem in France, which reaches to the very top.The local-election victory for Laurent Lopez, the FN candidate in the town of Brignoles, was a defeat for both left and right. The centre-right UMP, whose leaders never miss an opportunity to take pot-shots at each other, failed to persuade voters that it was the natural alternative to the Socialist-backed Communist incumbent. Eliminated in the first round, the left then failed to convince supporters to heed its call for a “republican” anti-FN vote in the run-off.Under France’s two-round voting system, which favours big parties, any FN victory is an impressive feat. That it has won in Brignoles, succeeding a Communist departmental councillor, marks…