Riots require critical mass to generate sufficient concentration of numbers.
This is why they happen in London but not small towns.
On any issue, a tiny % (far less than 0.1%) of people riot.
Imagine 0.1% in a town...
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Slough: 150 rioters
Kings Lynn: 43 rioters
Grimsby: 88 rioters
And so on.
These are numbers well above the typical turnout rate for a riot from within a population - and are unlikely to generate anonymity effects for crowd behaviour.
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e.g.
Birmingham: 1,100 rioters
London: 8,800 rioters
This reaches critical mass that can snowball. Hence riots happen sometimes.
But these are not leave heartlands and have police authorities experienced with protests and crowds.
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