The video of the tearful mother on Question Time explaining to Cabinet minister Amber Rudd what losing her tax credits will mean is everywhere today. The audience member also revealed that she had voted Conservative in May because, she said, “I thought you were going to be the better chance for me and my children”.

This video has been one of the most emotive examples of the impact of the Tories’ tax credit cuts to date, which is why it has been so widely shared. But the clip has also revealed the more unpleasant side of the left on social media, with people judging this poor woman for the way she voted.

She believed that the Tories would provide a better government for her family. I disagree, but I can relate to that decision. If even she, breaking down on television in desperation, is not good enough for the Labour Party, then who is?

If Labour is to win in 2020 it will need the votes of people like her. In fact, we will also need the votes of people who voted Tory and aren’t being hit by tax credit cuts. This is not up for debate: there is no way to win without their support.

The progressive majority myth, the non-voter myth, the mountain to climb – it all points to winning over Tories.

It’s all well and good sitting there and tweeting how we said this would happen, happy in the knowledge that we are not to blame. Labour does have to shoulder some blame for this, because we did not make a strong enough case that we could support people’s families. That’s why people voted for five more years of David Cameron. An a priori belief that Tories are evil does not amount to a strong enough case for Labour being in power to people who do not share that unshakeable faith.

Fear tactics may be successful in politics, but smug I Told You Sos are not.

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