I am struggling at the moment to think of anyone I know who hasn’t recently been called a Tory by someone. I know I – a member of the Labour Party for over 25 years – have been. And I’m not. But then neither are lots of other people.

For example, Liz Kendall isn’t a Tory. I know, that’s a little bit shocking right? Because over the last few weeks you’ll have heard little else. Here’s the thing though. Liz has been a Labour MP since 2010. That wasn’t a great year for us. If she were actually a Tory – or at least any good at being so – she’d be on the other side of the House having a much better time of it. If she were genuinely either a bit more careerist or right wing, frankly there are easier ways to do and be both than to try and lead the Labour Party.

But then you know who else aren’t Tories – Andy Burnham and Yvette Cooper. The Labour Party have had a difficult week where a combination of George Osborne and our own most noisy supporters have tried to force us into a complicated place on welfare. Our response may not have been as overt as those who think Labour’s only job is to oppose! oppose! oppose! (as opposed to get elected and actually change anything). It was complicated and Parliamentary (we sort of opposed the Welfare Bill while not opposing the good parts. No one will ever put this stance on a T Shirt) but abstaining to fight a line by line fight another day does not make you a Tory.

But then simply by being a member of the Labour Party, even Jeremy Corbyn has been called a Tory. For some on the far left, their perspective is so skewed that they can’t see anything to their right – even by the smallest of degrees – as legitimate. And in those circles the best and easiest way to de-legitimise anyone is to simply brand them a Tory and have done with it. By believing in Parliamentary democracy and the collectivism that makes the Labour Party such a broad church, that makes even Jeremy – in some eyes – a Tory.

But it’s harder than that. Because there are other people we like to dismiss as Tories who simply aren’t. Tony Blair for a start. I’m not always his biggest fan. I don’t agree with everything he did as Prime Minister. But he did do good things. Including winning and installing Labour governments. From which we got the Tax credits people are so concerned about in the first place. They may be imperfect. Tony may have been an imperfect leader. But he was a man on the Labour right who was elected in 1983 on that manifesto. No careerist Tory did that. Tony might have tried to change the Labour Party – and he may have gone too far on occasion even for this moderate’s blood – but he loved it and is still a part of it.

Which brings me to the last group of people who aren’t Tories. The most complicated group of all: Tory voters.

To us – who live and breath politics so much that we spend our days on political blogs arguing the ins and outs of the minutiae of politics – political identity is core to our being. I am Labour. I was born Labour and I will die Labour. It’s not an unquestioning loyalty – I frequently have existential crises about the state of the Party and politics more general – but it is such an essential part of who I am it is hard sometimes to remember how unusual that is. Whether you come here because you love or hate Labour you are likely to have read this far because you have relatively strong political opinions.

Most people don’t. Many of those who voted Tory at the last election or even the last few elections would not – if stopped on the street – identify themselves as a Tory. Yet we insist on writing them off as such. Deciding that someone is “once a Tory always a Tory” is to decide that we have no persuasive arguments to make; no good story to tell. That’s not true and it’s not how Labour will ever win again.

It’s not much fun being a member of the Labour Party at the moment. We are midway through at least a decade out of power. We are seeing the real Tories – those in government – dismantle the things we care for. It is natural after a defeat as bad as ours to circle the wagons emotionally. to close in on ourselves. But we can’t. We owe it to the people Labour is there to represent to be a Party that is open to all who are interested in our values. No more purity tests that we can only ever fail. Leave that to the unelectable.

Think hard before you next write someone off as a Tory. Could they have been you at one point? If so, then surely we want to convince not condemn them. That’s how you elect a government. That’s how you change lives.