“If children are taught in crumbling buildings and oversized classes, with too few textbooks and without personal, individual care, then they are not an investment for future wealth but an investment for future welfare,” Mrs Liddell said.

She added: “There is a crisis facing Scottish education that cannot be overestimated or ignored.” Scotland had been overtaken by countries “willing to learn and wanting to enjoy the material prosperity which the better-off in the West took for granted for generations”.

That was the global challenge for Labour. “There is no point in seeking the winners in the next century among those cavorting on the playing-fields of Eton. We will have to go to the state schools of Scotland to find them.”