There is no law of politics that states that a party must live forever. If the circumstances that brought it into existence change fundamentally and the party cannot or will not adapt, it will die. Anyone who supposes that the Labour Party has some kind of God-given right to permanent existence simply because it has been around for 116 years ought to look to Billingshurst in West Sussex, where the skeleton of a dodo is expected to fetch £500,000 at auction in October.

Even if Owen Smith wins the leadership contest, that dodo might well be a picture of perky good health compared to Labour by the end of the autumn party conference season. In 1845 the Tory supporters of Sir Robert Peel seemed to be the way of the future. Full of ideas, brilliant young leaders and intellectual self-confidence, they had reformed Britain profoundly and were about to lay the foundations of Victorian mid-century prosperity. Yet within a year, the battle over the repeal of the Corn Laws had left the Peelites broken and dispersed, their party wrecked by ideological in-fighting. British politics saw its first fundamental realignment of modern times, and the Tories did not form another majority government for 28 years.