The Labour leadership contest has, on the whole, not been a pretty sight. The ‘Corbyn surge’ has been accompanied by mounting vitriol across the factional divides, who accuse each other variously of being ‘Tory scum’ or ‘morons’ in need of a ‘heart transplant’. Whilst some level of rancour is to be expected in any political contest, there are worrying signs that the peculiarly progressive obsession with purity will doom Labour to the political wilderness just as certainly as either a stale continuation of New Labour or a radical hard-left policy platform ever will.

There is an irony at the heart of many forms of progressivism that whilst outwardly championing diversity and difference, progressives seem to love nothing more than defining themselves against their enemies and competing for who can most aggressively shun those with views outside the ‘acceptable’. To see this desperate desire for purity in action look no further than the much-loved ‘never kissed a Tory’ T-shirts worn by leftie LGBT groups, or the aggressive rhetoric of ‘smashing the BNP’ employed by groups like Unite Against Fascism. Such language betrays an implicit ‘progressive test’ used to determine whether an individual or group is worthy of engagement based on whether they subscribe to the right beliefs or not. I identified this approach as a key barrier to social and cultural integration at a grass-roots level in my Theos report Making Multiculturalism Work. But the petty name-calling of the Labour Leadership election is another classic example of the ‘progressive test’ taken to its logical extreme, as the barriers to who is ‘in’ and who is ‘out’ become narrower and narrower.

The problem with the progressive test is two-fold. The first is that it is in the end self-defeating as a way of combating extreme or unpleasant views. Refusing to engage or dialogue with individuals or groups that hold ‘non-progressive’ views is a terrible way to challenge those ideas, as it tends only to strengthen conservative forces who can easily develop a narrative of persecution which feeds off ostracism. In the end people change and soften their views through relationships, and so denying someone a relationship until they believe the ‘right’ things is about as self-defeating as it comes.

The second problem with the progressive test approach is that it is politically suicidal, as Labour may be about to find out. In a democracy, politics is ultimately a game of building consensus around a particular project, whether that’s a policy, a person or a party.  For whoever ends up as the next Labour leader, the task of building a big enough tent to pose a serious challenge in 2020 is already a daunting one. If the walls of that tent are set so high that anyone who has voted for the Conservatives or UKIP are deemed hopelessly neoliberal or reactionary then it’s very difficult to imagine anyone winning enough ‘pure’ converts to build political momentum.

The signs are not good that Labour can overcome this progressive paradox. Whilst commentators like Owen Jones have realised that “UKIP voters must be love-bombed” in order for a Corbyn-led Labour Party to be successful, it is difficult to imagine the idealistic new generation of supporters and members having the discipline and capacity for compromise that is needed to make such an approach successful.

A consequence of the current controversy over Corbyn’s relationships in the Middle East could easily be a future over-sensitivity to the threat of being ‘tainted’ by association with anybody who might potentially have extreme and unpleasant views. That is of course not to say that Corbyn has done no wrong in this instance, but merely to observe that it would in the end be extremely damaging to lose sight of his argument that “to bring about a peace process, you have to talk to people with whom you may profoundly disagree.”

Whoever Labour’s new Leader is, if they can’t help the Party develop an authentic yet open attitude to dealing with difference then the forces of progressive purity could in the end be crippling. Because the future of the Labour Party may well depend not just on which person gets to the top or which policies get promoted, but also whether it becomes a Party of the ‘progressive test’ or a genuinely broad-based movement for change.

David Barclay is the author of the Theos Report Making Multiculturalism Work and is the Faith in Public Life Officer at the Centre for Theology & Community.

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Image by Garry Knight from wikipedia.org available in the public domain