Rochester by-election: A little respect goes a long way, Ed Miliband

David Cameron could not believe his luck. He was about to lose a by-election to the most irritating bunch of people a moderate Conservative prime minister could imagine, when Ed Miliband decided to distract journalists with a class-based comedy caper.

One of Cameron's aides was so astonished by the Opposition's mistake that he could hardly contain himself when we spoke the next day. The gist, with the expletives deleted, was that Miliband and his advisers had lost possession of their faculties, but this was mixed with outrage at their sheer lack of professionalism, as if he felt his craft had been insulted.

"The broadcasters were unsure if they were going to report it," he said, of Emily Thornberry's condescending tweet about England flags and a white van in Strood. "So they phoned Ed Miliband's office and were briefed that he had never been so angry. It was like putting petrol on a fire." Worse, Miliband then decided that the story was so embarrassing that he should make it more so, by sacking Thornberry from her front-bench post of shadow Attorney General. This was such an odd decision I thought that it could not have been his. I assumed that she had been so ashamed of her lapse of judgement and so annoyed by the ridicule that she must have said, "Right, that's it; I'm off." But no: it seems that Miliband thought that she should go – and, presumably, that he would look like a strong leader if she did.

Thornberry's tweet seemed trivial, but it was important and it was embarrassing. The more so when journalists phoned to speak to her about it and, instead of saying she had tweeted the photo because she admired the show of patriotism, she said she thought the flags were "extraordinary" and that she had "never seen a house like it". But, once she had apologised, Labour could have said: "She shouldn't have done it; she's apologised; the Conservatives have lost a seat." If pressed about the leader's view, they could have said he was working on his plans for more apprentices.

The Sun would still have put White Van Dan on its front page, and a lot of people would still have said how silly Thornberry was, or that she was being unfairly hounded - as Katy Guest does today. But the broadcasters, the BBC in particular, would have been less interested in the story, partly because it would seem to be being run by the Conservative press. And the big story on Friday would have been that Ukip had doubled its representation in the House of Commons.

That is all about media handling, which matters because much of politics is about expectations and morale. By the time of the by-election, the Tories were pleased to lose by only 7 percentage points, which means they have a good chance of winning the seat back next year. But the underlying problem for Labour is its uncertain relationship with a large group of working-class voters. And Miliband is quite capable of making a mess of that on his own. When he was asked on Friday what goes through his mind when he sees a white van outside a house, he replied: "Respect."

This is what is known as the George H W Bush Error. President Bush Snr once opened a press conference by saying he was "in the business of lowering expectations here". His aides had their heads in their hands. That was his brief. He wasn't supposed to read it out, he was supposed to do it. Miliband had obviously had a discussion with, say, Douglas Alexander, chair of general election strategy, about how to deal with questions about Thornberry's apparent disdain for some voters. We have to show "respect, deep and real respect, for the hopes, aspirations and dreams of the people we seek to serve", Alexander might have said. I guess this because that is a line from the speech he gave in Stirling on Friday night.

Unfortunately for the Labour Party, Miliband's show of respect for the white working-class people he seeks to serve was no more authentic than Thornberry's tweeted apology: "People should fly the England flag with pride!" Mark Reckless, in his victory speech at 4.15 on Friday morning, made plain – again – Ukip's aim of recruiting Labour's working-class voters. Labour MPs tell me that their disaffected constituents are much more likely to vote Ukip than they are to vote Conservative – there is a taboo about the Tories that doesn't apply to Ukip no matter how much "more Tory than Tory" Labour people claim it is.

Ukip does not have to be very successful in this to erode the advantage Labour has enjoyed from Ukip's being better at winning over Tory voters than Labour ones. The white-van episode exposes the soft underbelly of Miliband's support and its vulnerability to sustained attack from Ukip and the Tories. This is one of the big issues of the next six months. It is getting late in the day and Labour is armed only with fake respect and a tin ear.

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