@OneInterestingFact Per my comment above, Israel's extreme model is a product of apartheid. I see zero prospect of the UK adopting that model.
A better example is the fate of Ireland’s Labour Party post-2011.
The radical left formed People Before Profit (#PBP), the soft left formed the Social Democrats. Irish Labour is struggling, as is PBP, but the SocDems are thriving.
A similar fate awaits UK Labour. The Labour left will escape its #StockholmSyndrome.