I can't remember where I read about the Ultimatum Game, if it was on here I apologise.
There's an economics experiment called the Ultimatum Game. It's played by two people. Person 1 is given a sum of money and has to propose to Person 2 how they split it. Person 2 then has to choose whether to accept or reject Person 1's proposal. If Person 2 accepts the proposal they both get the amount proposed by Person 1 and if Person 2 rejects the proposal neither of them gets any money at all. Logically speaking Person 2 should accept almost any offer. After all even a 99% - 1% split in favour of Person 1 will leave Person 2 better off than rejecting the offer. People's minds don't work that way though. Many people, if they see the offer as unfair, reject it even though that decision means they end up worse off as well.
I think a similar thing is happening here. A large part of society feels that a smaller part of society is getting an unfair share in various ways and in response they're choosing to reject the whole deal, choosing to reject mainstream politics and politicians. Michael Moore gets it:
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I should point out the video has been clipped and he goes on to point out that the good feeling will last maybe a month before people realise Trump is no better than anyone else and may well be much worse in many ways.
I linked to the Ulimatum game either on here or another forum over the past couple of days.