The bulk of the shadow chancellor’s speech today was about the economy and jobs. A Labour government, he said, would “plan for the future”, “intervene for the common good”, and “create the well-paid jobs we need”.

He made this pledge, however, without explaining how Labour would tackle the greatest threat to jobs that our society faces.

To be fair, Mr McDonnell isn’t alone in this. His counterparts in other parties have said little about it too. In the next 20 years, great numbers of people – working-class and middle-class – stand to be made redundant by advances in automation, artificial intelligence, and the internet. Yet major politicians are barely talking about it.

I suppose we’ve been here before. Mass immigration from eastern EU states began in 2004, but mainstream parties treated it as a serious issue only after the breakthrough of Ukip a decade later. Nigel Farage may feel that he’s now won that argument. But, if so, he’s won it too late. There is a bigger crisis coming – and when it arrives, it won’t be possible to blame it on foreigners.

Previously, Mr McDonnell has said Labour will “look at” the idea of a universal basic income – which would in theory save the obsolete from destitution. Provided he can work out how to pay for it, anyway.

Today, though, we heard him mourning Britain’s “dead town centres”, without noting that what killed them – primarily, online shopping – is unlikely to prove a passing fad. He talked about creating “secure” jobs, without explaining how any job will be secure in a world where technology outperforms mere humans.

The shadow chancellor – like the rest of the political world – sounded as if he was planning for a future that has already gone.