in a nutshell.

The defence of Corbyn is not the defence of an individual, even an admirable and, as the present situation shows, extremely brave one, but the defence of a possibility (and at the moment it is only a possibility) that Labour can offer and generate alternative purposes to those given by existing economic, political and social power. To defend Corbyn is also, though, to will and then engage in the thought and practical effort required to resolve the serious problems articulating, defending and finding ways to institutionalise and implement a modern socialist programme

Good blog post from Tom Gann