IT TAKES courage to mess with one of France’s most-loved brands. The public adores its TGV—Train à Grande Vitesse—as a symbol of modernity, and because many families dreamily associate the double-decker trains with long summer holidays. Yet from July 2nd, in time for les vacances, the state-owned railways, SNCF, will do away with the three-letter marque: the TGV service will be renamed “InOui”.

The change comes at a fateful time. On July 1st Emmanuel Macron, the president, will flag off France’s ninth and tenth high-speed routes, serving the country’s west. Rennes will be just an hour and a half from Paris. Yet no more entirely new lines are being built after these. The Rennes track alone consumed many billions of euros in a decade of construction. A report in 2014 by the public auditor found the lines rarely bring cities wider economic benefits.