""An old lesson taught at business schools about two ice cream sellers on a beach is useful. If a beach is four hundred yards long, it would make sense for the two sellers to position themselves a hundred yards from the middle and a hundred yards from either end. No one would be more than a hundred yards from an ice cream.
However, in the end each seller inches towards the middle. Those to the outside of him can be taken for granted. Those in the middle are there to be fought for. And so the two ice cream sellers end up side by side in the middle of the beach. The very same thing happens with mainstream political parties in two party systems.
But taken for granted in the analogy is that is a nice sunny day, and that everybody wants an ice cream.
The beach that Jeremy Corbyn must now inch his way across is more like Normandy on D-Day. Brexiteer has his machine guns turned on Remainer (or the other way round, if you prefer). Young is at war with old. A housing crisis splits the country into owners and renters. One generation has been greatly enriched by obscene property price inflation, while the same thing has smashed to smithereens the hopes and dreams of another.