I think that's a good question and one I've been interested in for a bit - the disjuncture between a neo-liberal consensus, a capitalist realism, lack of confidence in any kind of alternatives - and apparently large numbers of people willing to do something about it. As such, this isn't intended as a pissing on chips post, but in one sense the answer is that it's going nowhere in the short term. Labour will lose badly and Corbyn will either resign or, ultimately, be forced out. It will be very difficult to bring these numbers out for anything after the election and Labour's membership numbers are apparently in free fall.
I suppose the real answer in terms of it going nowhere is that it's going nowhere because it's gone nowhere in the last 18 months. Rallies, a few campaigns, some attempts at organising beyond the party's traditional places (I believe, but haven't seen much of it). Shoehorning 500,000 into the Labour Party hasn't achieved much, it's just been a dispiriting stand off with the right and, more importantly, it hasn't become something else, a social movement or reinvigorated working class politics. There are signs as to what might have been with the reception Labour's nationalisation policies have had, but they don't seem to be shaking the polls. Very hard to see where it goes - whilst the press and commentariat will be yapping away about the need for a new generation of Blairites to lead the party, there's neither the energy, personnel or ideas for that to happen. But equally, it's hard to see an effective social democratic leadership starting the whole thing off again.
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