Yet even Umunna fears to tackle what voters are most concerned about, and criticises the debate for focusing too much on numbers.

Well, Chuka, mate, if the scale of immigration is what voters want to talk about – if it’s the numbers that are causing concern – then however uncomfortable it makes you feel, you’d better talk about it. The alternative is to condescend to voters, lecture them on what they should actually care about, rather than address directly what they’re actually worried about.

This is a dilemma that would have presented itself even in the absence of an EU referendum. Labour MPs have seen what happened in Scotland when the Labour brand became no longer relevant to voters’ priorities. They’re painfully aware that at last year’s general election Ukip came second in a swathe of seats in Labour’s northern heartlands.