Two years after the crowds at Glastonbury burst into joyous chants of “Oh, Jeremy Corbyn!” the music festival has taken a darkly menacing turn — booking bands that have called for the children of Conservatives to be killed and that have staged the assassination of Theresa May.

The violence of the lyrics and imagery prompted Catherine Anderson, chief executive of the Jo Cox Foundation, to say last night: “We as a foundation cannot but think of Jo when any public platform is given to an individual or a group who are inciting violence. That sort of language and the abuse of children and family members should not be tolerated.”

Cox, the Labour MP, was murdered by a political extremist during the Brexit referendum campaign three