When you talk to a Conservative MP about the transformation of the Labour Party, they often sound as if they were discussing a death in the family. The tone is especially funereal if the MP in question happens to be from the party’s liberal wing.

This is not just because of their fear that Jeremy Corbyn will win the next election, or because of the friendships they formed with Corbyn-sceptic Labour MPs during the referendum campaign, but because they have no doubt that something similar could happen to them.

Membership of their party has been in steady decline since they came to office in 2010, to the point where the party now earns more from the legacies of dead members than it does from living