There is mob psychology and mob rule. Both which often arises with the help of divide-and-conquer excitation from above.
Then there are cults. Cults are often just mob psychology, and even mob rule, sustained over time, at a chronic, sub-acute, slow-motion level of activity. Cults tend to like narcotics, whereas mobs might prefer crack.
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And then there is BOM AND DOM, sex cult of the devils. )