From Corbynism: A Critical Approach, by Frederick Harry Pitts and Matt Bolton, loc 3122
It is the Corbyn movement’s reliance on this kind of hyper-moralised Schmittian identitarian politics of ‘friend’ and ‘enemy’ which explains why the Corbyn movement appears at its strongest when it comes under attack from internal or external foes, real or imagined, while dwindling into passivity in their absence. If socialism is a reflexive response to the natural, unchanging, essential desires of ontologically ‘good’ people, an innate ‘goodness’ which is embodied in or anchored around the person of Corbyn himself, then calling into question the character of Corbyn in any way casts doubt upon the movement’s own position as the prefiguration of the society to come, a society in which all contradiction and difference will be dissolved in the name of humanity’s unified moral nature. The need to continually defend Corbyn’s moral status from those ‘enemies’ who would ‘smear’ it acts as the negative force binding the movement together, preventing its internal contradictions from rising to the surface.
The obvious retort is to point out that it’s precisely the tendency of all mass movements to react in this way that makes the friend/enemy distinction so apt. It’s possible that Corbynism might be an unusually pronounced example of it, though it’s far from clear to me that they’ve established that. However what seems implausible is that it’s somehow unique in these characteristics, as a movement which mobilises the passions of hundreds of thousands of people.