To paraphrase Mark Twain, the age of politicians is an issue of mind over matter. If the voters don’t mind, the age of their leaders doesn’t matter. The election of Emmanuel Macron, 39, as France’s youngest head of state since Napoleon Bonaparte is part of a trend that is catapulting a clutch of youthful politicians into positions of leadership. This is all the more remarkable since most European countries have greying populations.

Recent examples include Leo Varadkar, 38, whom the Irish legislature has elected as the nation’s youngest ever premier, and Juri Ratas, who was also 38 when he became Estonia’s prime minister in November. Since recovering its independence in 1991, Estonia has made a habit of choosing young leaders. Taavi Roivas, Mr Ratas’s predecessor, was 34 when he took up the job in 2014.

When Austrians go to the polls in October, there is every chance that the winner will be